Data exchange method and apparatus

ABSTRACT

The present invention relates to a data exchange method and apparatus. The method includes: sending, by a primary base station, a request of setting up an X3 interface to a secondary base station, wherein the X3 interface has a capability of bidirectional data communication; receiving, by the primary base station, a response of setting up the X3 interface sent by the secondary base station; and performing, by the primary base station, bidirectional data exchange with the secondary base station by using the X3 interface.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/814,940 filed on Jul. 31, 2015, which is a continuation ofInternational Patent Application No. PCT/CN2013/071263 filed on Feb. 1,2013, the disclosures of the aforementioned applications are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

The present invention relates to the field of mobile communications, andin particular, to a data exchange method and apparatus.

BACKGROUND

With development of communications technologies and growing popularityof intelligent terminals, service traffic carried by wireless networksis growing rapidly. To meet such growth and improve experience of a userof a wireless terminal, a wireless network needs to provide a user witha higher bandwidth and a faster service rate.

For a Long Term Evolution (LTE) system, technologies such as coordinatedmulti-point transmission/reception (CoMP) and carrier aggregation (CA)are introduced in Release 10 and Release 11 to improve performance.

Topics such as inter-eNB CoMP (inter eNB CoMP), inter-evolved NodeBcarrier aggregation (inter evolved NodeB CA, inter eNB CA), and smallcell enhancement are further proposed in discussion of Release 12 of the3rd Generation Partnership Project (3GPP), aiming to provide a user withbetter service quality.

In all the foregoing technologies, at least two base stations arerequired to serve same user equipment (User Equipment, UE), so as toincrease a data exchange rate between UE and a network side. Therefore,how to implement that at least two base stations can simultaneouslyprovide service for one piece of UE becomes an urgent-settling issue.

SUMMARY

In view of this, a data exchange method and apparatus are provided, soas to implement that at least two base stations work together to provideservice for a same piece of UE.

According to a first aspect, a data exchange method is provided, and themethod includes:

receiving, by a secondary base station, a first message sent by aprimary base station, or receiving relationship information of asecondary base station and a primary base station configured by anoperation, administration and maintenance system OAM, where the firstmessage is used for notifying the secondary base station to set up an S1interface;

sending, by the secondary base station, an S1 interface setup request tothe primary base station;

receiving an S1 interface setup response sent by the primary basestation; and

performing, by the secondary base station, exchange with the primarybase station by using the S1 interface.

In a first possible implementation manner of the first aspect, the firstmessage carries an inter-eNB coordinated service identifier, the S1interface setup request carries an inter-base station coordinatedservice identifier, and/or the S1 interface setup response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the first aspect, preferably,the first message is sent by the primary base station after the primarybase station receives the relationship information of the secondary basestation and the primary base station from the OAM.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the first aspect, the methodfurther includes: receiving, by the secondary base station, an InternetProtocol IP address and a tunnel endpoint identifier TEID of the primarybase station that are sent by the primary base station; and theperforming, by the secondary base station, exchange with the primarybase station by using the S1 interface includes: sending, by thesecondary base station to the primary base station, received uplink datasent by user equipment UE, so that the primary base station sends theuplink data to a serving gateway S-GW; and/or receiving, by thesecondary base station, downlink data that is from the S-GW and isforwarded by the primary base station, and sending the downlink data tothe UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the first aspect, after thereceiving an S1 interface setup response sent by the primary basestation, the method further includes: sending, by the secondary basestation, a downlink transport network layer address TNL address and aGeneral Packet Radio Service Tunneling Protocol tunnel endpointidentifier GTP TED of the secondary base station to the primary basestation, so that the primary base station sends the downlink TNL addressand the GTP TEID of the secondary base station to an S-GW by using amobility management entity MME, and the secondary base station receivesan uplink TNL address and a GTP TED of the S-GW that are sent by theprimary base station; and the method further includes: sending, by thesecondary base station to the S-GW, received uplink data sent by UE, andsending, by the secondary base station to the UE, received downlink datasent by the S-GW.

According to a second aspect, a data exchange method is provided, andthe method includes:

sending, by a primary base station, a first message to a secondary basestation, where the first message is used for notifying the secondarybase station to set up an S1 interface;

receiving, by the primary base station, an S1 interface setup requestsent by the secondary base station;

sending an S1 interface setup response to the secondary base station;and

performing, by the primary base station, exchange with the secondarybase station by using the S1 interface.

In a first possible implementation manner of the second aspect, thefirst message carries an inter-base station coordinated serviceidentifier, the S1 interface setup request carries an inter-base stationcoordinated service identifier, and/or the S1 interface setup responsecarries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the second aspect, the sending,by a primary base station, a first message to a secondary base stationincludes: receiving, by the primary base station, relationshipinformation of the secondary base station and the primary base stationfrom an operation, administration and maintenance system OAM, andsending the first message to the secondary base station.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the second aspect, the methodfurther includes: sending, by the primary base station, an InternetProtocol IP address and a tunnel endpoint identifier TED of the primarybase station to the secondary base station; and the performing, by theprimary base station, exchange with the secondary base station by usingthe S1 interface includes: receiving, by the primary base station,uplink data that is from user equipment UE and is forwarded by thesecondary base station, and sending, by the primary base station, theuplink data to a serving gateway S-GW; and/or forwarding, to thesecondary base station, downlink data from the S-GW, so that thesecondary base station sends the downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the second aspect, after thesending an S1 interface setup response to the secondary base station,the method further includes: sending, by the primary base station to anS-GW by using a mobility management entity MME, a received downlinktransport network layer address TNL address and a received GeneralPacket Radio Service Tunneling Protocol tunnel endpoint identifier GTPTEID of the secondary base station that are sent by the secondary basestation, and sending, by the primary base station, an uplink TNL addressand a GTP TEID of the S-GW to the secondary base station, so that thesecondary base station sends, to the S-GW, received uplink data sent byUE, and sends, to the UE, received downlink data sent by the S-GW.

According to a third aspect, a data exchange method is provided, and themethod includes:

sending, by a primary base station, an X2 handover request message to asecondary base station, where the X2 handover request message includestunnel address information allocated by the primary base station to userequipment UE;

receiving, by the primary base station, an X2 handover request responsesent by the secondary base station; and

performing, by the primary base station, data exchange with thesecondary base station by using an X2 interface.

In a first possible implementation manner of the third aspect, thetunnel address information includes: a transport network layer addressTNL address and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier GTP TEID that are allocated by the primary basestation to the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the third aspect, the X2handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the third aspect, the methodfurther includes: updating or releasing, by the primary base station, anX2 interface association or a GTP tunnel related to the UE, and sendingan update or release message to the secondary base station, so that thesecondary base station updates or releases the X2 interface associationor the General Packet Radio Service Tunneling Protocol GTP tunnel of theUE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the third aspect, the update orrelease message carries the inter-base station coordinated serviceidentifier and a bearer identifier.

According to a fourth aspect, a data exchange method is provided, andthe method includes:

receiving, by a secondary base station, an X2 handover request messagesent by a primary base station, where the X2 handover request messageincludes tunnel address information allocated by the primary basestation to user equipment UE;

sending an X2 handover request response to the primary base station; and

performing, by the secondary base station, data exchange with theprimary base station by using an X2 interface.

In a first possible implementation manner of the fourth aspect, thetunnel address information includes: a transport network layer addressTNL address and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier GTP TEID that are allocated by the primary basestation to the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the fourth aspect, the X2handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the fourth aspect, the methodfurther includes: receiving, by the secondary base station, an update orrelease message sent by the primary base station, and updating orreleasing, by the secondary base station, an X2 interface association ora General Packet Radio Service Tunneling Protocol GTP tunnel of the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the fourth aspect, the updateor release message carries the inter-base station coordinated serviceidentifier and a bearer identifier.

According to a fifth aspect, a data exchange method is provided, and themethod includes:

sending, by a primary base station, a request of setting up an X3interface to a secondary base station, where the X3 interface has acapability of bidirectional data communication;

receiving, by the primary base station, a response of setting up the X3interface sent by the secondary base station; and

performing, by the primary base station, bidirectional data exchangewith the secondary base station by using the X3 interface.

In a first possible implementation manner of the fifth aspect, therequest of setting up the X3 interface carries an inter-base stationcoordinated service identifier, and/or the response of setting up the X3interface carries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the fifth aspect, the X3interface includes: an S1 interface.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the fifth aspect, the methodfurther includes: sending, by the primary base station, an InternetProtocol IP address and a tunnel endpoint identifier TED of the primarybase station to the secondary base station; and the performing, by theprimary base station, bidirectional data exchange with the secondarybase station by using the X3 interface includes: receiving, by theprimary base station, uplink data that is sent by user equipment UE andforwarded by the secondary base station, and sending the uplink data toa serving gateway S-GW; and sending, by the primary base station to thesecondary base station, downlink data sent by the S-GW, so that thesecondary base station sends the downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the fifth aspect, after thereceiving, by the primary base station, a response of setting up the X3interface sent by the secondary base station, the method furtherincludes: sending, by the primary base station, a downlink transportnetwork layer address TNL address and a General Packet Radio ServiceTunneling Protocol tunnel endpoint identifier GTP TEID of the secondarybase station to an S-GW by using a mobility management entity MME, andsending, by the primary base station, an uplink TNL address and a GTPTEID of the S-GW to the secondary base station, so that the secondarybase station sends, to the S-GW, received uplink data sent by UE, andsends, to the UE, received downlink data sent by the S-GW.

According to a sixth aspect, a data exchange method is provided, themethod including:

receiving, by a secondary base station, a request of setting up an X3interface sent by a primary base station, where the X3 interface has acapability of bidirectional data communication;

sending, by the secondary base station, a response of setting up the X3interface to the primary base station; and

performing, by the secondary base station, bidirectional data exchangewith the primary base station by using the X3 interface.

In a first possible implementation manner of the sixth aspect, therequest of setting up the X3 interface carries an—inter base stationcoordinated service identifier, and/or the response of setting up the X3interface carries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the sixth aspect, the X3interface includes: an S1 interface.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the sixth aspect, the methodfurther includes: receiving, by the secondary base station, an InternetProtocol IP address and a tunnel endpoint identifier TEID of the primarybase station that are sent by the primary base station; and theperforming, by the secondary base station, bidirectional data exchangewith the primary base station by using the X3 interface includes:sending, by the secondary base station to the primary base station,uplink data from user equipment UE, so that the primary base stationsends the uplink data to a serving gateway S-GW; and receiving, by thesecondary base station, downlink data that is from the S-GW and is sentby the primary base station, and sending the downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the sixth aspect, after thesending, by the secondary base station, a response of setting up the X3interface to the primary base station, the method further includes:receiving, by the secondary base station, an uplink transport networklayer address TNL address and a General Packet Radio Service TunnelingProtocol tunnel endpoint identifier GTP TED of an S-GW that are sent bythe primary base station; sending, to the S-GW, received uplink datasent by UE; and sending, to the UE, received downlink data from theS-GW.

According to a seventh aspect, a data exchange method is provided, andthe method includes:

receiving, by a mobility management entity MME, a first message sent bya primary base station, where the first message is used for requesting asecondary base station to collaborate with the primary base station toserve user equipment UE;

sending a second message to the secondary base station, where the secondmessage is used for requesting the secondary base station to collaboratewith the primary base station to serve the UE;

receiving a first response returned by the secondary base station, wherethe first response carries information that the secondary base stationagrees to collaborate with the primary base station to serve the UE; and

sending a second response to the primary base station, so that theprimary base station and the secondary base station work together toserve the UE.

In a first possible implementation manner of the seventh aspect, afterthe receiving a first response returned by the secondary base station,the method further includes: notifying a serving gateway S-GWcorresponding to the UE of address information of the secondary basestation, and notifying the secondary base station of address informationof the S-GW, so that the secondary base station performs data exchangewith the S-GW for the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the seventh aspect, the addressinformation of the secondary base station includes: a transport networklayer address TNL address and a General Packet Radio Service TunnelingProtocol tunnel endpoint identifier GTP-TEID of the secondary basestation, and the address information of the S-GW includes: a TNL addressand a GTP-TEID of the S-GW.

According to an eighth aspect, a data exchange method is provided, andthe method includes:

receiving, by a secondary base station, a second message sent by amobility management entity MME, where the second message is used forrequesting the secondary base station to collaborate with a primary basestation to serve user equipment UE; and

sending, by the secondary base station, a first response to the MME,where the first response carries information that the secondary basestation agrees to collaborate with the primary base station to serve theUE, so that the MME sends a second response to the primary base station,where the second response is used for notifying that the primary basestation works together with the secondary base station to serve the UE.

In a first possible implementation manner of the eighth aspect, afterthe sending, by the secondary base station, a first response to the MME,the method further includes: receiving, by the secondary base station,address information, sent by the MME, of a serving gateway S-GWcorresponding to the UE; and performing, by the secondary base stationaccording to the address information of the S-GW, data exchange with theS-GW for the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the eighth aspect, the addressinformation of the S-GW includes: a transport network layer address TNLaddress and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier GTP-TEID of the S-GW.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the eighth aspect, theperforming, by the secondary base station according to the addressinformation of the S-GW, data exchange with the S-GW for the UEincludes: sending, by the secondary base station to the S-GW, receiveduplink data from the UE, and sending, to the UE, received downlink datafrom the S-GW.

According to a ninth aspect, a data exchange apparatus is provided,where the apparatus is a secondary base station, and the apparatusincludes: a receiving unit, a sending unit, and an exchange unit, where

the receiving unit is configured to receive a first message sent by aprimary base station, or receive relationship information of thesecondary base station and a primary base station configured by anoperation, administration and maintenance system OAM, where the firstmessage is used for notifying the secondary base station to set up an S1interface;

the sending unit is configured to send an S1 interface setup request tothe primary base station;

the receiving unit is configured to receive an S1 interface setupresponse sent by the primary base station; and

the exchange unit is configured to perform exchange with the primarybase station by using the S1 interface.

In a first possible implementation manner of the ninth aspect, the firstmessage carries an inter-base station coordinated service identifier,the S1 interface setup request carries an inter-base station coordinatedservice identifier, and/or the S1 interface setup response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the ninth aspect, the firstmessage is sent by the primary base station after the primary basestation receives the relationship information of the secondary basestation and the primary base station from the OAM.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the ninth aspect, the receivingunit is configured to receive an Internet Protocol IP address and atunnel endpoint identifier TEID of the primary base station that aresent by the primary base station; and the exchange unit is configuredto: send, to the primary base station, received uplink data sent by userequipment UE, so that the primary base station sends the uplink data toa serving gateway S-GW; and/or receive downlink data that is from theS-GW and is forwarded by the primary base station, and send the downlinkdata to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the ninth aspect, the sendingunit is further configured to send a downlink transport network layeraddress TNL address and a General Packet Radio Service TunnelingProtocol tunnel endpoint identifier GTP TEID of the secondary basestation to the primary base station, so that the primary base stationsends the downlink TNL address and the GTP TEID of the secondary basestation to an S-GW by using a mobility management entity MME, and thesecondary base station receives an uplink TNL address and a GTP TEID ofthe S-GW that are sent by the primary base station; and the sending unitis further configured to send, to the S-GW, received uplink data sent byUE, and send, to the UE, received downlink data sent by the S-GW.

According to a tenth aspect, a data exchange apparatus is provided,where the apparatus is a primary base station, and the apparatusincludes: a sending unit, a receiving unit, and an exchange unit, where

the sending unit is configured to send a first message to a secondarybase station, where the first message is used for notifying thesecondary base station to set up an S1 interface;

the receiving unit is configured to receive an S1 interface setuprequest sent by the secondary base station;

the sending unit is further configured to send an S1 interface setupresponse to the secondary base station; and

the exchange unit is configured to perform exchange with the secondarybase station by using the S1 interface.

In a first possible implementation manner of the tenth aspect, the firstmessage carries an inter base station coordinated service identifier,the S1 interface setup request carries an inter-base station coordinatedservice identifier, and/or the S1 interface setup response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the tenth aspect, the receivingunit is further configured to receive relationship information of thesecondary base station and the primary base station from an OAM, and thesending unit is further configured to send the first message to thesecondary base station.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the tenth aspect, the sendingunit is further configured to send an IP address and a TEID of theprimary base station to the secondary base station; and the exchangeunit is configured to: receive uplink data that is sent by the secondarybase station and received from user equipment UE, and send the uplinkdata to an S-GW; and/or forward, to the secondary base station, downlinkdata from the S-GW, so that the secondary base station sends thedownlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the tenth aspect, the sendingunit is further configured to send, to an S-GW by using an MME, areceived downlink TNL address and a received GTP TEID of the secondarybase station that are sent by the secondary base station, and send anuplink TNL address and a GTP TEID of the S-GW to the secondary basestation, so that the secondary base station sends, to the S-GW, receiveduplink data sent by UE, and the secondary base station sends, to the UE,received downlink data sent by the S-GW.

According to an eleventh aspect, a data exchange apparatus is provided,where the apparatus is a primary base station, and the apparatusincludes: a sending unit, a receiving unit, and an exchange unit, where

the sending unit is configured to send an X2 handover request message toa secondary base station, where the X2 handover request message includestunnel address information allocated by the primary base station to userequipment UE;

the receiving unit is configured to receive an X2 handover requestresponse sent by the secondary base station; and

the exchange unit is configured to perform data exchange with thesecondary base station by using an X2 interface.

In a first possible implementation manner of the eleventh aspect, thetunnel address information includes: a transport network layer addressTNL address and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier GTP TEID that are allocated by the primary basestation to the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the eleventh aspect, the X2handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the eleventh aspect, theapparatus further includes: a control unit, configured to update orrelease an X2 interface association or a GTP tunnel related to the UE,and the sending unit is further configured to send an update or releasemessage to the secondary base station, so that the secondary basestation updates or releases the X2 interface association or the GeneralPacket Radio Service Tunneling Protocol GTP tunnel of the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the eleventh aspect, the updateor release message carries the inter-base station coordinated serviceidentifier and a bearer identifier.

According to a twelfth aspect, a data exchange apparatus is provided,where the apparatus is a secondary base station, and the apparatusincludes: a receiving unit, a sending unit, and an exchange unit, where

the receiving unit is configured to receive an X2 handover requestmessage sent by a primary base station, where the X2 handover requestmessage includes tunnel address information allocated by the primarybase station to user equipment UE;

the sending unit is configured to send an X2 handover request responseto the primary base station; and

the exchange unit is configured to perform data exchange with theprimary base station by using an X2 interface.

In a first possible implementation manner of the twelfth aspect, thetunnel address information includes: a transport network layer addressTNL address and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier GTP TEID that are allocated by the primary basestation to the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the twelfth aspect, the X2handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the twelfth aspect, thereceiving unit is configured to receive an update or release messagesent by the primary base station; and the apparatus further includes: acontrol unit, configured to update or release an X2 interfaceassociation or a General Packet Radio Service Tunneling Protocol GTPtunnel of the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the twelfth aspect, the updateor release message carries the inter-base station coordinated serviceidentifier and a bearer identifier.

According to a thirteenth aspect, a data exchange apparatus is provided,where the apparatus is a primary base station, and the apparatusincludes: a sending unit, a receiving unit, and an exchange unit, where

the sending unit is configured to send a request of setting up an X3interface to a secondary base station, where the X3 interface has acapability of bidirectional data communication;

the receiving unit is configured to receive a response of setting up theX3 interface sent by the secondary base station; and

the exchange unit is configured to perform bidirectional data exchangewith the secondary base station by using the X3 interface.

In a first possible implementation manner of the thirteenth aspect, therequest of setting up the X3 interface carries an inter-base stationcoordinated service identifier, and/or the response of setting up the X3interface carries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the thirteenth aspect, the X3interface includes: an S1 interface.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the thirteenth aspect, thesending unit is further configured to send an Internet Protocol IPaddress and a tunnel endpoint identifier TEID of the primary basestation to the secondary base station; and the exchange unit isconfigured to: receive uplink data that is sent by user equipment UE andforwarded by the secondary base station, and send the uplink data to aserving gateway S-GW; and send, to the secondary base station, downlinkdata sent by the S-GW, so that the secondary base station sends thedownlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the thirteenth aspect, thesending unit is further configured to send a downlink transport networklayer address TNL address and a General Packet Radio Service TunnelingProtocol tunnel endpoint identifier GTP TEID of the secondary basestation to an S-GW by using an MME, and send an uplink TNL address and aGTP TEID of the S-GW to the secondary base station, so that thesecondary base station sends, to the S-GW, received uplink data sent byUE, and sends, to the UE, received downlink data sent by the S-GW.

According to a fourteenth aspect, a data exchange apparatus is provided,where the apparatus is a secondary base station, and the apparatusincludes: a receiving unit, a sending unit, and an exchange unit, where

the receiving unit is configured to receive a request of setting up anX3 interface sent by a primary base station, where the X3 interface hasa capability of bidirectional data communication;

the sending unit is configured to send a response of setting up the X3interface to the primary base station; and

the exchange unit is configured to perform bidirectional data exchangewith the primary base station by using the X3 interface.

In a first possible implementation manner of the fourteenth aspect, therequest of setting up the X3 interface carries an inter-base stationcoordinated service identifier, and/or the response of setting up the X3interface carries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the fourteenth aspect, the X3interface includes: an S1 interface.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the fourteenth aspect, thereceiving unit is further configured to receive an Internet Protocol IPaddress and a tunnel endpoint identifier TEID of the primary basestation that are sent by the primary base station; the exchange unit isconfigured to send, to the primary base station, uplink data sent fromuser equipment UE, so that the primary base station sends the uplinkdata to a serving gateway S-GW; and the secondary base station receivesdownlink data that is sent by the primary base station and is from theS-GW, and sends the downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the fourteenth aspect, theexchange unit is further configured to: receive an uplink transportnetwork layer address TNL address and a General Packet Radio ServiceTunneling Protocol tunnel endpoint identifier GTP TEID of an S-GW thatare sent by the primary base station; send, to the S-GW, received uplinkdata sent by UE; and send, to the UE, received downlink data from theS-GW.

According to a fifteenth aspect, a data exchange apparatus is provided,where the apparatus is a mobility management entity MME, and theapparatus includes: a receiving unit and a sending unit, where

the receiving unit is configured to receive a first message sent by aprimary base station, where the first message is used for requesting asecondary base station to collaborate with the primary base station toserve user equipment UE;

the sending unit is configured to send a second message to the secondarybase station, where the second message is used for requesting thesecondary base station to collaborate with the primary base station toserve the UE;

the receiving unit is further configured to receive a first responsereturned by the secondary base station, where the first response carriesinformation that the secondary base station agrees to collaborate withthe primary base station to serve the UE; and

the sending unit is further configured to send a second response to theprimary base station, so that the primary base station and the secondarybase station work together to serve the UE.

In a first possible implementation manner of the fifteenth aspect, thesending unit is further configured to notify a serving gateway S-GWcorresponding to the UE of address information of the secondary basestation, and notify the secondary base station of address information ofthe S-GW, so that the secondary base station performs data exchange withthe S-GW for the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the fifteenth aspect, theaddress information of the secondary base station includes: a transportnetwork layer address TNL address and a General Packet Radio ServiceTunneling Protocol tunnel endpoint identifier GTP-TEID of the secondarybase station, and the address information of the S-GW includes: a TNLaddress and a GTP-TEID of the S-GW.

According to a sixteenth aspect, a data exchange apparatus is provided,where the apparatus is a secondary base station, and the apparatusincludes: a receiving unit and a sending unit, where

the receiving unit is configured to receive a second message sent by amobility management entity MME, where the second message is used forrequesting the secondary base station to collaborate with a primary basestation to serve user equipment UE; and

the sending unit is configured to send a first response to the MME,where the first response carries information that the secondary basestation agrees to collaborate with the primary base station to serve theUE, so that the MME sends a second response to the primary base station,where the second response is used for notifying that the primary basestation works together with the secondary base station to serve the UE.

In a first possible implementation manner of the sixteenth aspect, thereceiving unit is further configured to receive address information,sent by the MME, of a serving gateway S-GW corresponding to the UE; andthe apparatus further includes an exchange unit, configured to perform,according to the address information of the S-GW, data exchange with theS-GW for the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the sixteenth aspect, theaddress information of the S-GW includes: a transport network layeraddress TNL address and a General Packet Radio Service TunnelingProtocol tunnel endpoint identifier GTP-TEID of the S-GW.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the sixteenth aspect, theexchange unit is further configured to send, to the S-GW, receiveduplink data from the UE, and send, to the UE, received downlink datafrom the S-GW.

According to a seventeenth aspect, a data exchange apparatus isprovided, where the apparatus is a secondary base station, and theapparatus includes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for receiving a first message sent by a primary basestation, or receiving relationship information of the secondary basestation and a primary base station configured by an operation,administration and maintenance system OAM, where the first message isused for notifying the secondary base station to set up an S1 interface;

an instruction used for sending an S1 interface setup request to theprimary base station;

an instruction used for receiving an S1 interface setup response sent bythe primary base station; and

an instruction used for performing exchange with the primary basestation by using the S1 interface; and

the processor is configured to execute the application program.

In a first possible implementation manner of the seventeenth aspect, thefirst message carries an inter-base station coordinated serviceidentifier, the S1 interface setup request carries an inter-base stationcoordinated service identifier, and/or the S1 interface setup responsecarries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the seventeenth aspect, thefirst message is sent by the primary base station after the primary basestation receives the relationship information of the secondary basestation and the primary base station from the OAM.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the seventeenth aspect, theapplication program further includes: an instruction used for receivingan Internet Protocol IP address and a tunnel endpoint identifier TEID ofthe primary base station that are sent by the primary base station; andthe instruction used for performing exchange with the primary basestation by using the S1 interface includes: an instruction used forsending, to the primary base station, received uplink data sent by userequipment UE, so that the primary base station sends the uplink data toan S-GW; and/or an instruction used for receiving downlink data that isfrom the S-GW and is forwarded by the primary base station, and sendingthe downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the seventeenth aspect, theapplication program further includes: an instruction used for sending adownlink transport network layer address TNL address and a GeneralPacket Radio Service Tunneling Protocol tunnel endpoint identifier GTPTEID of the secondary base station to the primary base station, so thatthe primary base station sends the downlink TNL address and the GTP TEIDof the secondary base station to an S-GW by using an MME, and aninstruction used for receiving an uplink TNL address and a GTP TEID ofthe S-GW that are sent by the primary base station; and the applicationprogram further includes: an instruction used for sending, to the S-GW,received uplink data sent by UE, and sending, to the UE, receiveddownlink data sent by the S-GW.

According to an eighteenth aspect, a data exchange apparatus isprovided, where the apparatus is a primary base station, and theapparatus includes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for sending a first message to a secondary basestation, where the first message is used for notifying the secondarybase station to set up an S1 interface;

an instruction used for receiving an S1 interface setup request sent bythe secondary base station;

an instruction used for sending an S1 interface setup response to thesecondary base station; and

an instruction used for performing exchange with the secondary basestation by using the S1 interface; and

the processor is configured to execute the application program.

In a first possible implementation manner of the eighteenth aspect, thefirst message carries an inter-base station coordinated serviceidentifier, the S1 interface setup request carries an inter-base stationcoordinated service identifier, and/or the S1 interface setup responsecarries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the eighteenth aspect, theinstruction used for sending a first message to a secondary base stationincludes: an instruction used for receiving relationship information ofthe secondary base station and the primary base station from an OAM, andan instruction used for sending the first message to the secondary basestation.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the eighteenth aspect, theapplication program further includes: an instruction used for sending anInternet Protocol IP address and a tunnel endpoint identifier TEID ofthe primary base station to the secondary base station; and theinstruction used for performing exchange with the secondary base stationby using the S1 interface includes: an instruction used for receivinguplink data that is sent by the secondary base station and received fromuser equipment UE, and an instruction used for sending the uplink datato an S-GW; and/or an instruction used for forward, to the secondarybase station, downlink data from the S-GW, so that the secondary basestation sends the downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the eighteenth aspect, theapplication program further includes: an instruction used for sending,to an S-GW by using an MME, a received downlink TNL address and areceived GTP TEID of the secondary base station that are sent by thesecondary base station, and an instruction used for sending an uplinkTNL address and a GTP TEID of the S-GW to the secondary base station, sothat the secondary base station sends, to the S-GW, received uplink datasent by UE, and the secondary base station sends, to the UE, receiveddownlink data sent by the S-GW.

According to a nineteenth aspect, a data exchange apparatus is provided,where the apparatus is a primary base station, and the apparatusincludes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for sending an X2 handover request message to asecondary base station, where the X2 handover request message includestunnel address information allocated by the primary base station to userequipment UE;

an instruction used for receiving an X2 handover request response sentby the secondary base station; and

an instruction used for performing data exchange with the secondary basestation by using an X2 interface; and

the processor is configured to execute the application program.

In a first possible implementation manner of the nineteenth aspect, thetunnel address information includes: a transport network layer addressTNL address and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier GTP TEID that are allocated by the primary basestation to the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the nineteenth aspect, the X2handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the nineteenth aspect, theapplication program further includes: an instruction used for updatingor releasing an X2 interface association or a GTP tunnel related to theUE, and sending an update or release message to the secondary basestation, so that the secondary base station updates or releases the X2interface association or the General Packet Radio Service TunnelingProtocol GTP tunnel of the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the nineteenth aspect, theupdate or release message carries the inter-base station coordinatedservice identifier and a bearer identifier.

According to a twentieth aspect, a data exchange apparatus is provided,where the apparatus is a secondary base station, and the apparatusincludes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for receiving an X2 handover request message sent bya primary base station, where the X2 handover request message includestunnel address information allocated by the primary base station to userequipment UE;

an instruction used for sending an X2 handover request response to theprimary base station; and

an instruction used for performing data exchange with the primary basestation by using an X2 interface; and

the processor is configured to execute the application program.

In a first possible implementation manner of the twentieth aspect, thetunnel address information includes: a transport network layer addressTNL address and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier GTP TEID that are allocated by the primary basestation to the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the twentieth aspect, the X2handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the twentieth aspect, theapplication program further includes: an instruction used for receivingan update or release message sent by the primary base station, andupdating or releasing an X2 interface association or a General PacketRadio Service Tunneling Protocol GTP tunnel of the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the twentieth aspect, theupdate or release message carries the inter-base station coordinatedservice identifier and a bearer identifier.

According to a twenty-first aspect, a data exchange apparatus isprovided, where the apparatus is a primary base station, and theapparatus includes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for sending a request of setting up an X3 interfaceto a secondary base station, where the X3 interface has a capability ofbidirectional data communication;

an instruction used for receiving a response of setting up the X3interface sent by the secondary base station; and

an instruction used for performing bidirectional data exchange with thesecondary base station by using the X3 interface; and

the processor is configured to execute the application program.

In a first possible implementation manner of the twenty-first aspect,the request of setting up the X3 interface carries an inter-base stationcoordinated service identifier, and/or the response of setting up the X3interface carries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the twenty-first aspect, the X3interface includes: an S1 interface.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the twenty-first aspect, theapplication program further includes: an instruction used for sending anInternet Protocol IP address and a tunnel endpoint identifier TEID ofthe primary base station to the secondary base station; and theinstruction used for performing bidirectional data exchange with thesecondary base station by using the X3 interface includes: aninstruction used for receiving uplink data that is sent by userequipment UE and forwarded by the secondary base station, and sendingthe uplink data to a serving gateway S-GW; and an instruction used forsending, to the secondary base station, downlink data sent by the S-GW,so that the secondary base station sends the downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the twenty-first aspect, theapplication program further includes: an instruction used for sending,after the primary base station receives the response of setting up theX3 interface sent by the secondary base station, a downlink transportnetwork layer address TNL address and a General Packet Radio ServiceTunneling Protocol tunnel endpoint identifier GTP TEID of the secondarybase station to an S-GW by using a mobility management entity MME, andan instruction used for sending an uplink TNL address and a GTP TEID ofthe S-GW to the secondary base station, so that the secondary basestation sends, to the S-GW, received uplink data sent by UE, and aninstruction used for sending, to the UE, received downlink data sent bythe S-GW.

In a twenty-second aspect, a data exchange apparatus is provided, wherethe apparatus is a secondary base station, and the apparatus includes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for receiving a request of setting up an X3interface sent by a primary base station, where the X3 interface has acapability of bidirectional data communication;

an instruction used for sending a response of setting up the X3interface to the primary base station; and

an instruction used for performing bidirectional data exchange with theprimary base station by using the X3 interface; and

the processor is configured to execute the application program.

In a first possible implementation manner of the twenty-second aspect,the request of setting up the X3 interface carries an inter-base stationcoordinated service identifier, and/or the response of setting up the X3interface carries an inter-base station coordinated service identifier.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the twenty-second aspect, theX3 interface includes: an S1 interface.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the twenty-second aspect, theapplication program further includes: an instruction used for receivingan Internet Protocol IP address and a tunnel endpoint identifier TEID ofthe primary base station that are sent by the primary base station; andthe instruction used for performing bidirectional data exchange with theprimary base station by using the X3 interface includes: an instructionused for sending, to the primary base station, uplink data from userequipment UE, so that the primary base station sends the uplink data toa serving gateway S-GW; and an instruction used for receiving downlinkdata that is from the S-GW and is sent by the primary base station, andsending the downlink data to the UE.

According to one of the foregoing possible implementation manners, in afourth possible implementation manner of the twenty-second aspect, theapplication program further includes: an instruction used for receivingan uplink transport network layer address TNL address and a GeneralPacket Radio Service Tunneling Protocol tunnel endpoint identifier GTPTEID of an S-GW that are sent by the primary base station, sending, tothe S-GW, received uplink data sent by UE, and sending, to the UE,received downlink data from the S-GW.

According to a twenty-third aspect, a data exchange apparatus isprovided, where the apparatus is a mobility management entity MME, andthe apparatus includes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for receiving a first message sent by a primary basestation, where the first message is used for requesting a secondary basestation to collaborate with the primary base station to serve userequipment UE;

an instruction used for sending a second message to the secondary basestation, where the second message is used for requesting the secondarybase station to collaborate with the primary base station to serve theUE;

an instruction used for receiving a first response returned by thesecondary base station, where the first response carries informationthat the secondary base station agrees to collaborate with the primarybase station to serve the UE; and

an instruction used for sending a second response to the primary basestation, so that the primary base station and the secondary base stationwork together to serve the UE; and

the processor is configured to execute the application program.

In a first possible implementation manner of the twenty-third aspect,the application program further includes: an instruction used fornotifying a serving gateway S-GW corresponding to the UE of addressinformation of the secondary base station, and notifying the secondarybase station of address information of the S-GW, so that the secondarybase station performs data exchange with the S-GW for the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the twenty-third aspect, theaddress information of the secondary base station includes: a transportnetwork layer address TNL address and a General Packet Radio ServiceTunneling Protocol tunnel endpoint identifier GTP-TEID of the secondarybase station, and the address information of the S-GW includes: a TNLaddress and a GTP-TEID of the S-GW.

According to a twenty-fourth aspect, a data exchange apparatus isprovided, where the apparatus is a secondary base station, and theapparatus includes:

a network interface;

a processor;

a memory; and

an application program stored in the memory, where the applicationprogram includes:

an instruction used for receiving a second message sent by a mobilitymanagement entity MME, where the second message is used for requestingthe secondary base station to collaborate with a primary base station toserve user equipment UE; and

an instruction used for sending a first response to the MME, where thefirst response carries information that the secondary base stationagrees to collaborate with the primary base station to serve the UE, sothat the MME sends a second response to the primary base station, wherethe second response is used for notifying that the primary base stationworks together with the secondary base station to serve the UE; and

the processor is configured to execute the application program.

In a first possible implementation manner of the twenty-fourth aspect,after the secondary base station sends the first response to the MME,the application program further includes: an instruction used forreceiving address information, sent by the MME, of a serving gatewayS-GW corresponding to the UE; and an instruction used for performing,according to the address information of the S-GW, data exchange with theS-GW for the UE.

According to one of the foregoing possible implementation manners, in asecond possible implementation manner of the twenty-fourth aspect, theaddress information of the S-GW includes: a transport network layeraddress TNL address and a General Packet Radio Service TunnelingProtocol tunnel endpoint identifier GTP-TEID of the S-GW.

According to one of the foregoing possible implementation manners, in athird possible implementation manner of the twenty-fourth aspect, theinstruction used for performing, according to the address information ofthe S-GW, data exchange with the S-GW for the UE includes: aninstruction used for sending, to the S-GW, received uplink data from theUE, and sending, to the UE, received downlink data from the S-GW.

For the data exchange method and apparatus in the embodiments of thepresent invention, an S1, X2 or X3 interface between a primary basestation and a secondary base station may be used to perform, or asecondary base station may be used to directly perform, datatransmission with an S-GW, thereby implementing data exchange betweenthe primary base station and the secondary base station; coordinateddata transmission is performed, and the primary base station may performbidirectional data transmission with the secondary base station, therebyimproving service quality for UE.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of a data exchange method according to a firstembodiment of the present invention;

FIG. 2 is a flowchart of a data exchange method according to a secondembodiment of the present invention;

FIG. 3 is a flowchart of a data exchange method according to a thirdembodiment of the present invention;

FIG. 4 is a flowchart of a data exchange method according to a fourthembodiment of the present invention;

FIG. 5 is a flowchart of a data exchange method according to a fifthembodiment of the present invention;

FIG. 6 is a flowchart of a data exchange method according to a sixthembodiment of the present invention;

FIG. 7 is a flowchart of a data exchange method according to a seventhembodiment of the present invention;

FIG. 8 is a flowchart of a data exchange method according to an eighthembodiment of the present invention;

FIG. 9 is a schematic diagram of a data exchange apparatus according toa first embodiment of the present invention;

FIG. 10 is a schematic diagram of a data exchange apparatus according toa second embodiment of the present invention;

FIG. 11 is a schematic diagram of a data exchange apparatus according toa third embodiment of the present invention;

FIG. 12 is a schematic diagram of a data exchange apparatus according toa fourth embodiment of the present invention;

FIG. 13 is a schematic diagram of a data exchange apparatus according toa fifth embodiment of the present invention;

FIG. 14 is a schematic diagram of a data exchange apparatus according toa sixth embodiment of the present invention;

FIG. 15 is a schematic diagram of a data exchange apparatus according toa seventh embodiment of the present invention;

FIG. 16 is a schematic diagram of a data exchange apparatus according toan eighth embodiment of the present invention;

FIG. 17 is a schematic diagram of another data exchange apparatusaccording to a first embodiment of the present invention;

FIG. 18 is a schematic diagram of another data exchange apparatusaccording to a second embodiment of the present invention;

FIG. 19 is a schematic diagram of another data exchange apparatusaccording to a third embodiment of the present invention;

FIG. 20 is a schematic diagram of another data exchange apparatusaccording to a fourth embodiment of the present invention;

FIG. 21 is a schematic diagram of another data exchange apparatusaccording to a fifth embodiment of the present invention;

FIG. 22 is a schematic diagram of another data exchange apparatusaccording to a sixth embodiment of the present invention;

FIG. 23 is a schematic diagram of another data exchange apparatusaccording to a seventh embodiment of the present invention; and

FIG. 24 is a schematic diagram of another data exchange apparatusaccording to an eighth embodiment of the present invention.

DETAILED DESCRIPTION

The technical solutions of the present invention are further describedbelow in detail with reference to the accompanying drawings andembodiments.

In the embodiments of the present invention, a base station eNB1 and abase station eNB2 may work together to serve UE, where eNB1 is a primaryserving base station, and eNB2 is a secondary serving base station, ormay also be referred to as a secondary base station, a coordinating basestation, a small cell node, a low power node, a relay station, a homebase station, a small-cell base station, a micro base station, a picobase station, a macro base station, or the like. In the embodiments ofthe present invention, there may be one secondary base station, or theremay be multiple secondary base stations.

FIG. 1 and FIG. 2 are flowcharts of data exchange methods according to afirst embodiment and a second embodiment of the present invention. Thefirst embodiment illustrates a processing process of a primary basestation, and the second embodiment illustrates a processing process of asecondary base station. The primary base station and the secondary basestation in the first embodiment and the second embodiment performexchange by using an S1 interface.

FIG. 1 is a flowchart of a data exchange method according to the firstembodiment of the present invention. As shown in the figure, the methodin this embodiment includes the following steps:

Step 101: A secondary base station receives a first message sent by aprimary base station, or receives relationship information of thesecondary base station and a primary base station configured by anoperation, administration and maintenance system, where the firstmessage is used for notifying the secondary base station to set up an S1interface.

For example, a primary base station eNB1 expects to set up the S1interface with a secondary base station eNB2, from the perspective ofthe secondary base station eNB2, the primary base station eNB1 isconsidered as a special core network node, and therefore, the primarybase station eNB1 may perform UE context management and bearermanagement on the secondary base station eNB2. For example, UE contextmanagement and bearer management procedures in 3GPP TS 36.413 of theS1AP protocol are used between the primary base station eNB1 and thesecondary base station eNB2.

Optionally, the S1 interface is an S1 interface used for an inter-basestation coordinated service, and an S1 interface setup requirement S1SETUP REQUIRED/INVOKE message carries an inter-base station coordinatedservice identifier. For example, a field for recording a name in the S1interface setup requirement includes information about an inter-basestation coordinated service.

The inter-base station coordinated service may be inter-base stationcoordinated transmission, inter-base station CoMP, inter-base stationcarrier aggregation, an inter-base station multiflow service, or thelike.

In this step, the primary base station eNB1 sends the S1 interface setuprequirement to the secondary base station eNB2, so that the secondarybase station eNB2 learns that the primary base station eNB1 expects toset up the S1 interface with the secondary base station eNB2. Thesecondary base station eNB2 may learn that, in other manners, theprimary base station eNB1 expects to set up the S1 interface with thesecondary base station eNB2. For example:

The operation, administration and maintenance system (OAM) sends therelationship information configured by the OAM to the primary basestation and/or the secondary base station; and/or the S1 interface setuprequirement carries an inter-base station coordinated serviceidentifier.

The relationship information is a corresponding relationship between aprimary base station and a secondary base station, or a correspondingrelationship between a controlling node and a controlled node.

Step 102: The secondary base station sends an S1 interface setup requestto the primary base station.

For example, after receiving the S1 interface setup requirement, orreceiving the relationship information sent by the OAM, the secondarybase station eNB2 learns that the primary base station eNB1 needs thesecondary base station eNB2 to request to assist the primary basestation eNB1 in serving UE. If the secondary base station eNB2 agrees,the secondary base station eNB2 sends the S1 interface setup request S1SETUP REQUEST message to the primary base station eNB1. The setuprequest is sent from the secondary base station eNB2 to the primary basestation eNB1, and may carry an inter-base station coordinated serviceidentifier.

Step 103: Receive an S1 interface setup response sent by the primarybase station.

If the primary base station eNB1 allows the S1 interface setup, theprimary base station eNB1 sends the S1 interface setup response S1 SETUPRESPONSE message to the secondary base station, where the message maycarry an inter-base station coordinated service identifier. If theprimary base station eNB1 does not allow the S1 interface setup, theprimary base station eNB1 returns an S1 setup failure S1 SETUP FAILUREmessage to the secondary base station.

Step 104: The secondary base station performs exchange with the primarybase station by using the S1 interface. For example, an S1 interfaceconnection is set up between the secondary base station and the primarybase station, and data exchange is performed by using the S1 interface.

The S1 interface is set up between the primary base station eNB1 and thesecondary base station eNB2, and subsequently functions of UE contextmanagement and bearer management are reused to implement an inter-basestation coordinated transmission service. From the perspective of theUE, the S1 interface of the UE may be connected to a mobility managemententity (MME) by using eNB1. In the prior art, eNB2 does not directlyexchange information about the UE with a serving MME of the UE. In thisembodiment, eNB2 can be connected to the serving MME of the UE by usingthe S1 interface between eNB2 and eNB1, so that the information aboutthe UE can be exchanged with the serving MME of the UE.

Using the data exchange method in this embodiment, it is implementedthat after triggering by a primary base station or configuration by anOAM, a secondary base station initiates an S1 interface setup request,so as to set up an S1 interface that can be used to performbidirectional data transmission, thereby implementing that bidirectionaldata exchange is performed between the primary base station and thesecondary base station by using the S1 interface.

FIG. 2 is a flowchart of a data exchange method according to the secondembodiment of the present invention. As shown in the figure, the methodin this embodiment includes the following steps:

Step 201: A primary base station sends a first message to a secondarybase station, where the first message is used for notifying thesecondary base station to set up an S1 interface.

For example, a primary base station eNB1 expects to set up the S1interface with a secondary base station eNB2, from the perspective ofthe secondary base station eNB2, the primary base station eNB1 isconsidered as a special core network node, and therefore, the primarybase station eNB1 may perform UE context management and bearermanagement on the secondary base station eNB2. For example, UE contextmanagement and bearer management procedures in 3GPP TS 36.413 of theS1AP protocol are used between the primary base station eNB1 and thesecondary base station eNB2.

Optionally, the S1 interface is an S1 interface used for an inter-basestation coordinated service, and an S1 interface setup requirement S1SETUP REQUIRED/INVOKE message carries an inter-base station coordinatedservice identifier. For example, a field for recording a name in the S1interface setup requirement includes information about an inter-basestation coordinated service.

The inter-base station coordinated service may be inter-base stationcoordinated transmission, inter-base station CoMP, inter-base stationcarrier aggregation, an inter-base station multiflow service, or thelike.

In step 201, the primary base station eNB1 sends the S1 interface setuprequirement to the secondary base station eNB2, so that the secondarybase station eNB2 learns that the primary base station eNB1 expects toset up the S1 interface with the secondary base station eNB2, or thesecondary base station eNB2 may learn that, in other manners, theprimary base station eNB1 expects to set up the S1 interface with thesecondary base station eNB2. For example:

An operation, administration and maintenance system (OAM) sendsrelationship information configured by the OAM to the primary basestation and/or the secondary base station; and/or the S1 interface setuprequirement carries an inter-base station coordinated serviceidentifier.

The relationship information is a corresponding relationship between aprimary base station and a secondary base station, or a correspondingrelationship between a control node and a controlled node.

Step 202: The primary base station receives an S1 interface setuprequest sent by the secondary base station.

For example, after receiving the S1 interface setup requirement, orreceiving the relationship information sent by the OAM, the secondarybase station eNB2 learns that the primary base station eNB1 needs thesecondary base station eNB2 to request to assist the primary basestation eNB1 in serving UE. If the secondary base station eNB2 agrees,the secondary base station eNB2 sends the S1 interface setup request S1SETUP REQUEST message to the primary base station eNB1. The setuprequest is sent from the secondary base station eNB2 to the primary basestation eNB1, and may carry an inter-base station coordinated serviceidentifier.

Step 203: The primary base station sends an S1 interface setup responseto the secondary base station.

If the primary base station eNB1 allows the S1 interface setup, theprimary base station eNB1 sends the S1 interface setup response S1 SETUPRESPONSE message to the secondary base station, where the message maycarry an inter-base station coordinated service identifier. If theprimary base station eNB1 does not allow the S1 interface setup, theprimary base station eNB1 returns an S1 setup failure S1 SETUP FAILUREmessage to the secondary base station.

Step 204: The primary base station performs exchange with the secondarybase station by using the S1 interface. For example, an S1 interfaceconnection is set up between the primary base station and the secondarybase station, and data exchange is performed by using the S1 interface.

The S1 interface is set up between the primary base station eNB1 and thesecondary base station eNB2, and subsequently functions of UE contextmanagement and bearer management are reused to implement an inter-basestation coordinated transmission service.

Using the data exchange method in this embodiment, it is implementedthat after triggering by a primary base station or configuration by anOAM, a secondary base station initiates an S1 interface setup request,so as to set up an S1 interface that can be used to performbidirectional data transmission, thereby implementing that bidirectionaldata exchange is performed between the primary base station and thesecondary base station by using the S1 interface.

FIG. 3 and FIG. 4 are flowcharts of data exchange methods according to athird embodiment and a fourth embodiment of the present invention. Inthe third embodiment and the fourth embodiment, an X2 interface is usedto implement inter-base station data exchange.

As shown in FIG. 3, the method in the third embodiment includes thefollowing steps:

Step 301: A primary base station sends an X2 handover request message toa secondary base station, where the X2 handover request message includestunnel address information allocated by the primary base station to userequipment UE.

The X2 handover request message carries a transport network layer (TNL)address and a General Packet Radio Service (GPRS) Tunneling Protocol(GTP) tunnel endpoint identifier (TEID) that are allocated by theprimary base station eNB1 to the UE, or may carry a coordinated serviceidentifier at the same time, and the coordinated service identifier maybe an inter-base station coordinated transmission/service identifier, aninter-base station CoMP identifier, an inter-base station carrieraggregation service identifier, an inter-base station multiflow serviceidentifier, or the like.

Step 302: The primary base station eNB1 receives an X2 handover responsemessage returned by the secondary base station eNB2.

The secondary base station eNB2 receives the X2 handover requestmessage, and learns that the primary base station eNB1 expects that thesecondary base station eNB2 performs coordinated transmission for theUE. If the secondary base station eNB2 agrees, the secondary basestation eNB2 returns a handover response handover request acknowledgemessage to the primary base station eNB1, where the message may carry aninter-base station coordinated service identifier; if the secondary basestation eNB2 does not agree, the secondary base station eNB2 returns ahandover preparation failure Handover preparation failure message to theprimary base station eNB1.

Step 303: The secondary base station performs data exchange with theprimary base station by using an X2 interface. For example, an X2association and a bidirectional GTP tunnel of the UE are set up betweenthe primary base station eNB1 and the secondary base station eNB2, so asto perform data transmission by using the X2 interface.

In the prior art, during setup of an X2 interface, only a GTP tunnelfrom a primary base station to a secondary base station is set up, andtherefore, the X2 interface can only be used to perform unidirectionaldata transmission. In this embodiment, the X2 handover request messageincludes the tunnel address information allocated by the primary basestation to the user equipment UE, so that a GTP tunnel from thesecondary base station to the primary base station can be set up, and incombination with the prior art, a bidirectional GTP tunnel is set up.Therefore, the X2 interface set up in this embodiment can be used toperform bidirectional data transmission, thereby implementingbidirectional data exchange between the primary base station and thesecondary base station.

Preferably, as shown in FIG. 3, the method in this embodiment furtherincludes:

Step 304: The primary base station updates or releases an X2 interfaceassociation or a GTP tunnel related to the UE, and sends an update orrelease message to the secondary base station, so that the secondarybase station updates or releases the X2 interface association or the GTPtunnel of the UE. By means of this embodiment, when the primary basestation updates information related to the X2 interface, the secondarybase station also performs a corresponding update procedure. In thisway, the primary base station and the secondary base station haveconsistent information related to the X2 interface, and the primary basestation and the secondary base station may continue to perform exchangeby using the X2 interface. When the primary base station releases theinformation related to the X2 interface, the secondary base station alsoperforms a corresponding release procedure. In this way, a releasedresource may be used for another procedure, thereby improving systemperformance.

When the primary base station eNB1 requests the secondary base stationeNB2 to stop a coordinated service for the UE, the primary base stationeNB1 sends a release message, namely, a handover cancel message, to thesecondary base station eNB2 to release the association and the relatedGTP tunnel of the UE. Preferably, the message may carry an inter-basestation coordinated service identifier and/or a bearer identifier.

As shown in FIG. 4, the method in the fourth embodiment includes thefollowing steps:

Step 401: A secondary base station receives an X2 handover requestmessage sent by a primary base station, where the X2 handover requestmessage includes tunnel address information allocated by the primarybase station to user equipment UE.

The X2 handover request X2AP Handover request message carries atransport network layer (TNL) address and a GPRS Tunneling Protocol(GTP) tunnel endpoint identifier (TEID) that are allocated by theprimary base station eNB1 to the UE, or may carry a coordinated serviceidentifier at the same time, and the coordinated service identifier maybe an inter-base station coordinated transmission/service identifier, aninter-base station CoMP identifier, an inter-base station carrieraggregation service identifier, an inter-base station multiflow serviceidentifier, or the like.

Step 402: The secondary base station sends an X2 handover requestresponse to the primary base station.

The secondary base station eNB2 receives the X2 handover requestmessage, and learns that the primary base station eNB1 expects that thesecondary base station eNB2 performs coordinated transmission for theUE. If the secondary base station eNB2 agrees, the secondary basestation eNB2 returns a handover response Handover request acknowledgemessage to the primary base station eNB1, where the message may carry aninter-base station coordinated service identifier; if the secondary basestation eNB2 does not agree, the secondary base station eNB2 returns ahandover preparation failure Handover preparation failure message to theprimary base station eNB1.

Step 403: The secondary base station performs data exchange with theprimary base station by using an X2 interface. For example, an X2association and a bidirectional GTP tunnel of the UE are set up betweenthe secondary base station eNB2 and the primary base station eNB1, so asto perform data transmission by using the X2 interface.

In the prior art, during setup of an X2 interface, only a GTP tunnelfrom a primary base station to a secondary base station is set up, andtherefore, the X2 interface can only be used to perform unidirectionaldata transmission. In this embodiment, the X2 handover request messageincludes the tunnel address information allocated by the primary basestation to the user equipment UE, so that a GTP tunnel from thesecondary base station to the primary base station can be set up, and incombination with the prior art, a bidirectional GTP tunnel is set up.Therefore, the X2 interface set up in this embodiment can be used toperform bidirectional data transmission, thereby implementingbidirectional data exchange between the secondary base station and theprimary base station.

Preferably, as shown in FIG. 4, the method in this embodiment furtherincludes:

Step 404: The primary base station updates or releases an X2 interfaceassociation or a GTP tunnel related to the UE, the secondary basestation receives an update or release message sent by the primary basestation, and the secondary base station updates or releases the X2interface association or the GTP tunnel of the UE.

When the primary base station eNB1 requests the secondary base stationeNB2 to stop a coordinated service for the UE, the primary base stationeNB1 sends a release message, namely, a handover cancel message, to thesecondary base station eNB2 to release the association and the relatedGTP tunnel of the UE. Preferably, the message may carry an inter-basestation coordinated service identifier and/or a bearer identifier.

Using the X2AP handover method in Embodiment 3 and Embodiment 4, atransport network layer (TNL) address and a General Packet Radio Service(GPRS) Tunneling Protocol (GTP) tunnel endpoint identifier (TEID) of aprimary base station are also sent to a secondary base station.Therefore, bidirectional data transmission between the primary basestation and the secondary base station may be implemented by using anX2AP handover procedure. Alternatively, a UE context managementprocedure and a bearer management procedure may be added to the X2APprotocol, and are the same as those in the S1AP protocol.

FIG. 5 and FIG. 6 are flowcharts of data exchange methods according to afifth embodiment and a sixth embodiment of the present invention. In thefifth embodiment and the sixth embodiment, an X3 interface may be usedto perform data exchange.

As shown in FIG. 5, the method in the fifth embodiment includes thefollowing steps:

Step 501: A primary base station sends a request of setting up an X3interface to a secondary base station, where the X3 interface has acapability of bidirectional data communication.

For example, the X3 interface is an interface of an inter-base stationcoordinated service and may be implemented by using an S1 interface. Thesetup request is sent from a primary base station eNB1 to a secondarybase station eNB2, that is, the X3 interface setup is initiated from theprimary base station to the secondary base station, and in this case,the primary base station may be considered as a “core network device” towhich the secondary base station is connected.

The so-called X3 interface may be another existing interface, forexample, an existing S1 interface, or may be a newly defined interface,as long as information exchange can be implemented.

Preferably, the X3 interface setup request may be an X3 Setup Requestused for an inter-base station coordinated service. The X3 interfacesetup request carries an inter-base station coordinated serviceidentifier. The inter-base station coordinated service may be inter-basestation coordinated transmission/an inter-base station coordinatedservice, inter-base station CoMP, inter-base station carrieraggregation, an inter-base station multiflow service, or the like.

Step 502: The primary base station receives a response of setting up theX3 interface sent by the secondary base station.

If the secondary base station eNB2 agrees to set up the X3 interface,the secondary base station eNB2 returns an X3 interface setup responseX3 setup response message of the inter-base station coordinated serviceto the primary base station eNB1, where the response message may carryan inter-base station coordinated service identifier.

If the secondary base station eNB2 does not agree to set up the X3interface, the secondary base station eNB2 returns an X3 setup Failuremessage of the inter-base station coordinated service, where the X3setup Failure message may also carry an inter-base station coordinatedservice identifier.

Step 503: The primary base station performs bidirectional data exchangewith the secondary base station by using the X3 interface. For example,an X3 interface of UE is set up between the primary base station eNB1and the secondary base station eNB2, so as to perform data transmissionby using the X3 interface.

In this embodiment, a primary base station sends a request of setting upan X3 interface, so that the X3 interface from the primary base stationto a secondary base station can be set up, and the X3 interface may beimplemented by an existing interface, for example, an S1 interface, ormay be a newly defined interface having a capability of bidirectionaldata communication. Therefore, the X3 interface set up in thisembodiment can be used to perform bidirectional data transmission,thereby implementing bidirectional data exchange between the primarybase station and the secondary base station.

As shown in FIG. 6, the method in the sixth embodiment includes thefollowing steps:

Step 601: A secondary base station receives a request of setting up anX3 interface sent by a primary base station, where the X3 interface hasa capability of bidirectional data communication.

For example, the X3 interface is an interface of an inter-base stationcoordinated service and may be implemented by using an S1 interface. Thesetup request is sent from a primary base station eNB1 to a secondarybase station eNB2, that is, the X3 interface setup is initiated from theprimary base station to the secondary base station, and in this case,the primary base station may be considered as a “core network device” towhich the secondary base station is connected.

The so-called X3 interface may be another existing interface, forexample, an existing S1 interface, or may be a newly defined interface,as long as information exchange can be implemented.

Preferably, the X3 interface setup request may be an X3 Setup Requestused for an inter-base station coordinated service. The X3 interfacesetup request carries an inter-base station coordinated serviceidentifier. The inter-base station coordinated service may be inter-basestation coordinated transmission/an inter-base station coordinatedservice, inter-base station CoMP, inter-base station carrieraggregation, an inter-base station multiflow service, or the like.

Step 602: The secondary base station sends a response of setting up theX3 interface to the primary base station.

If the secondary base station eNB2 agrees to set up the X3 interface,the secondary base station eNB2 returns an X3 interface setup responseX3 setup response message of the inter-base station coordinated serviceto the primary base station eNB1, where the response message may carryan inter-base station coordinated service identifier.

If the secondary base station eNB2 does not agree to set up the X3interface, the secondary base station eNB2 returns an X3 setup Failuremessage of the inter-base station coordinated service, where the X3setup Failure message may also carry an inter-base station coordinatedservice identifier.

Step 603: The secondary base station performs bidirectional dataexchange with the primary base station by using the X3 interface. Forexample, an X3 interface of UE is set up between the secondary basestation eNB2 and the primary base station eNB1, so as to perform datatransmission by using the X3 interface.

In this embodiment, a secondary base station receives a request ofsetting up an X3 interface sent by a primary base station, so that theX3 interface from the secondary base station to the primary base stationcan be set up, and the X3 interface may be implemented by an existinginterface, for example, an S1 interface, or may be a newly definedinterface having a capability of bidirectional data communication.Therefore, the X3 interface set up in this embodiment can be used toperform bidirectional data transmission, thereby implementingbidirectional data exchange between the secondary base station and theprimary base station.

All the foregoing embodiments illustrate a process of interface setup orhandover. After the interface setup or handover, the secondary basestation eNB2 needs to be used to perform data exchange. The primary basestation eNB1 not only provides a function of an MME, but also provides afunction of a serving gateway (S-GW). The primary base station eNB1sends, to the secondary base station eNB2, an S-GW IP address and a GTPTED that are allocated by the primary base station.

From the perspective of a core network node, the primary base stationeNB1 is a serving base station of UE, and a core network sends data andcontrol signaling of the UE to the primary base station eNB1. Theprimary base station eNB1 forwards all or some of the data and controlsignaling of the UE to eNB2. The UE sends all or some of uplink data ofthe UE to the secondary base station eNB2, the secondary base stationeNB2 sends the received uplink data of the UE to the primary basestation eNB1, and the primary base station eNB1 then forwards the uplinkdata to an actual core network node S-GW.

The primary base station eNB1 is considered as a special core networknode by the secondary base station eNB2. The primary base stationprovides at least the following functions: a UE context managementfunction, a bearer management function, and an interface managementfunction.

The X3 interface in these embodiments is set up in a manner in which theprimary base station actively triggers a setup request, and thesecondary base station responds to the request. After the X3 interfaceis set up, the primary base station may provide the following functions:a UE context management function, a bearer management function, and aninterface management function.

In this case, the primary base station eNB1 is not included in a rangeof candidate core network nodes for a NAS node selection function (NNSF)procedure. That is, when UE is newly connected to the secondary basestation eNB2, and the UE is not UE for which the secondary base stationeNB2 needs to assist the primary eNB1 in transmission, the primary basestation eNB1 is not included in a range of candidates when eNB2 selectsa core network node for the UE.

In addition, the primary base station eNB1 provides a function of GTP-Utunnel mapping to implement a mapping between a GTP-U tunnel that isbetween the primary base station eNB1 and the S-GW and a GTP-U tunnelthat is between the primary base station eNB1 and the secondary basestation eNB2.

Optionally, the secondary base station eNB2 may also directly performdata exchange with the S-GW, and does not need to perform data exchangewith the S-GW by using the primary base station eNB1. After an S1interface is set up between the primary base station eNB1 and thesecondary base station eNB2, the primary base station eNB1 changes a TNLaddress and a GTP TEID in an S1AP message. It should be noted that thisembodiment may also be implemented as an independent embodiment.

Specifically, the primary base station eNB1 sends, to the S-GW by usingan MME, a received downlink TNL address and a received GTP TED of thesecondary base station that are sent by the secondary base station eNB2,and the primary base station eNB1 sends an uplink TNL address and a GTPTED of the S-GW to the secondary base station eNB2. Therefore, data of abearer of the UE transmitted by the secondary base station eNB2 isdirectly transmitted between eNB2 and the S-GW, the secondary basestation eNB2 sends, to the S-GW, received uplink data sent by the UE,and the secondary base station eNB2 sends, to the UE, received downlinkdata sent by the S-GW.

A primary base station may perform bidirectional data transmission witha secondary base station. Therefore, the secondary base station mayperform data exchange with an S-GW by using the primary base station.The secondary base station may also directly perform data exchange withthe S-GW. Therefore, for an inter-base station coordinated service,different base stations may serve different bearers, thereby improvingservice quality for UE. Existing messages are reused to the maximumdegree.

FIG. 7 and FIG. 8 are flowcharts of data exchange methods according to aseventh embodiment and an eighth embodiment of the present inventionrespectively. In all the foregoing embodiments, it is the primary basestation eNB1 that performs coordinated data exchange with the secondarybase station eNB2; in the seventh embodiment and the eighth embodiment,a core network may be used to perform assisted data exchange.

As shown in FIG. 7, the method in the seventh embodiment includes thefollowing steps:

Step 701: An MME receives a first message sent by a primary basestation, where the first message is used for requesting a secondary basestation to collaborate with the primary base station to serve userequipment UE. Preferably, the first message includes an identifier ofthe UE and an identifier of the secondary base station.

The primary base station eNB1 sends the first message to the MME torequest the secondary base station to collaborate with the primary basestation to serve the user equipment UE, where the first message maycarry the identifier of the UE, a bearer identifier, and the identifierof the collaborating secondary base station eNB2, so as to notify theMME that which secondary base station eNB2 is expected to coordinate.

Step 702: Send a second message to the secondary base station, where thesecond message is used for requesting the secondary base station tocollaborate with the primary base station to serve the UE. Preferably,the second message includes the identifier of the UE.

If the MME agrees on an inter-base station coordinated service request,the MME sends the second message, for example, an inter base stationcoordinated service request/command, to the coordinating secondary basestation eNB2 to request the secondary base station to collaborate withthe primary base station to serve the UE, where the inter-base stationcoordinated service request/command carries the identifier of the UE anda bearer identifier, and preferably, the inter-base station coordinatedservice request/command may further carry an identifier of the primarybase station.

Step 703: Receive a first response returned by the secondary basestation, where the first response carries information that the secondarybase station agrees to collaborate with the primary base station toserve the UE.

If the secondary base station eNB2 agrees on the request, the secondarybase station eNB2 sends the first response to the MME, where the firstresponse may be an inter-base station coordinated service responsemessage. If the secondary base station eNB2 does not agree on therequest, the secondary base station eNB2 returns a failure response.

The secondary base station may allow coordinated transmission of onlysome bearers, and in this case, the inter-base station coordinatedservice response message carries identifiers of bearers for whichcoordinated transmission is allowed.

The MME may determine, according to a bearer identifier carried in thecoordinated service response or a bearer identifier carried in theinter-base station coordinated service request in step 701, on whichbase station each bearer is transmitted; further, the MME may determine,according to load conditions of the primary base station and thesecondary base station and information about a bearer of the UE, onwhich base station each bearer is transmitted.

Step 704: Send a second response to the primary base station, so thatthe primary base station and the secondary base station work together toserve the UE. Data exchange is performed, between the secondary basestation and the MME and between the secondary base station and an S-GWcorresponding to the MME, for a bearer of the UE corresponding to theidentifier of the UE.

The MME sends the second response message to the primary base stationeNB1. If the secondary base station eNB2 does not agree on the request,the secondary base station eNB2 returns a failure response. The MMEsends, according to on which base station each bearer is transmitted, acorresponding TNL address and GTP-TEID to a corresponding node (theprimary base station eNB1 or the secondary base station eNB2). Thesecondary base station sends, to the S-GW, received uplink data sent bythe UE, and the secondary base station sends, to the UE, receiveddownlink data sent by the S-GW.

In the data exchange method in this embodiment, a network element MME ofa core network is used to assist in data exchange, thereby implementingthat a primary base station and a secondary base station work togetherto serve UE. The secondary base station is used to directly perform datatransmission with an S-GW, so that for an inter-base station coordinatedservice, different base stations may serve different bearers, therebyimproving service quality for UE. Existing messages are reused to themaximum degree.

As shown in FIG. 8, the method in the eighth embodiment includes thefollowing steps:

Step 801: A secondary base station receives a second message sent by anMME, where the second message is used for requesting the secondary basestation to collaborate with a primary base station to serve UE.Preferably, the second message includes a UE identifier.

The primary base station eNB1 sends a first message to the MME torequest the secondary base station to collaborate with the primary basestation to serve the user equipment UE, where the first message maycarry the identifier of the UE, a bearer identifier, and an identifierof the coordinating secondary base station eNB2, so as to notify the MMEthat which secondary base station eNB2 is expected to coordinate.

Step 802: The secondary base station sends a first response to the MME,where the first response carries information that the secondary basestation agrees on the first message of collaborating with the primarybase station to serve the UE, so that the MME sends a second response tothe primary base station.

If the MME agrees on an inter-base station coordinated service request,the MME sends the second message, for example, an inter-base stationcoordinated service request/command, to the coordinating secondary basestation eNB2 to request the secondary base station to collaborate withthe primary base station to serve the UE, where the inter-base stationcoordinated service request/command carries the identifier of the UE anda bearer identifier, and preferably, the inter-base station coordinatedservice request/command may further carry an identifier of the primarybase station.

If the secondary base station eNB2 agrees on the request, the secondarybase station eNB2 sends the first response, for example, an inter-basestation coordinated service response message, to the MME. If thesecondary base station eNB2 does not agree on the request, the secondarybase station eNB2 returns a failure response.

The secondary base station may allow coordinated transmission of onlysome bearers, and in this case, the inter-base station coordinatedservice response message carries identifiers of bearers for whichcoordinated transmission is allowed.

The MME may determine, according to a bearer identifier carried in thecoordinated service response or a bearer identifier carried in theinter-base station coordinated service request in step 801, on whichbase station each bearer is transmitted; further, the MME may determine,according to load conditions of the primary base station and thesecondary base station and information about a bearer of the UE, onwhich base station each bearer is transmitted.

Step 803: The primary base station and the secondary base station worktogether to serve the UE. Data exchange is performed, between thesecondary base station and the MME and between the secondary basestation and an S-GW corresponding to the MME, for a bearer of the UEcorresponding to the identifier of the UE.

The MME sends the related second response message to the primary basestation eNB1. If the secondary base station eNB2 does not agree on therequest, the secondary base station eNB2 returns a failure response. TheMME sends, according to on which base station each bearer istransmitted, a corresponding TNL address and GTP-TEID to a correspondingnode (the primary base station eNB1 or the secondary base station eNB2).The secondary base station sends, to the S-GW, received uplink data sentby the UE, and the S-GW sends, to the UE, received downlink data sent bythe S-GW.

In the data exchange method in this embodiment, a network element MME ofa core network is used to assist in data exchange, thereby implementingthat a primary base station and a secondary base station work togetherto serve UE. The secondary base station is used to directly perform datatransmission with an S-GW, so that for an inter-base station coordinatedservice, different base station may serve different bearers, therebyimproving service quality for UE. Existing messages are reused to themaximum degree.

FIG. 9 is a schematic diagram of a data exchange apparatus according toa first embodiment of the present invention. The apparatus in thisembodiment is a secondary base station, and as shown in the figure, thedata exchange apparatus in this embodiment specifically includes: areceiving unit 11, a sending unit 12, and an exchange unit 13.

The receiving unit 11 is configured to receive a first message sent by aprimary base station, or receive relationship information of thesecondary base station and a primary base station configured by anoperation, administration and maintenance system OAM, where the firstmessage is used for notifying the secondary base station to set up an S1interface; the sending unit 12 is configured to send an S1 interfacesetup request to the primary base station; the receiving unit 11 isfurther configured to receive an S1 interface setup response sent by theprimary base station; and the exchange unit 13 is configured to performexchange with the primary base station by using the S1 interface.

The exchange unit 13 may include the receiving unit 11 and/or thesending unit 12, or may be another unit having a sending and/orreceiving function.

Specifically, the first message carries an inter-base stationcoordinated service identifier, the S1 interface setup request carriesan inter-base station coordinated service identifier, and/or the S1interface setup response carries an inter-base station coordinatedservice identifier. The first message is sent by the primary basestation after the primary base station receives the relationshipinformation of the secondary base station and the primary base stationfrom the OAM.

Preferably, the receiving unit 11 is further configured to receive anInternet Protocol IP address and a tunnel endpoint identifier TED of theprimary base station that are sent by the primary base station; and theexchange unit 13 is configured to: send, to the primary base station,received uplink data sent by user equipment UE, so that the primary basestation sends the uplink data to a serving gateway S-GW; and/or receivedownlink data that is from the S-GW and is forwarded by the primary basestation, and send the downlink data to the UE.

Preferably, the sending unit 12 is further configured to send a downlinktransport network layer address TNL address and a General Packet RadioService Tunneling Protocol tunnel endpoint identifier GTP TEID of thesecondary base station to the primary base station, so that the primarybase station sends the downlink TNL address and the GTP TED of thesecondary base station to an S-GW by using a mobility management entityMME, and the secondary base station receives an uplink TNL address and aGTP TEID of the S-GW that are sent by the primary base station; and thesending unit 12 is further configured to send, to the S-GW, receiveduplink data sent by the UE, and send, to the UE, received downlink datasent by the S-GW.

The data exchange apparatus in this embodiment implements that asecondary base station initiates an S1 interface setup request aftertriggering by a primary base station or configuration by an OAM, so asto set up an S1 interface that can be used to perform bidirectional datatransmission, thereby implementing that bidirectional data exchange isperformed between the primary base station and the secondary basestation by using the S1 interface.

FIG. 10 is a schematic diagram of a data exchange apparatus according toa second embodiment of the present invention. The apparatus in thisembodiment is a primary base station, and as shown in the figure, thedata exchange apparatus in this embodiment specifically includes: asending unit 21, a receiving unit 22, and an exchange unit 23.

The sending unit 21 is configured to send a first message to a secondarybase station, where the first message is used for notifying thesecondary base station to set up an S1 interface; the receiving unit 22is configured to receive an S1 interface setup request sent by thesecondary base station; the sending unit 21 is further configured tosend an S1 interface setup response to the secondary base station; andthe exchange unit 23 is configured to perform exchange with thesecondary base station by using the S1 interface.

The exchange unit 23 may include the sending unit 21 and/or thereceiving unit 22, or may be another unit having a sending and/orreceiving function.

Preferably, the first message carries an inter-base station coordinatedservice identifier, the S1 interface setup request carries an inter-basestation coordinated service identifier, and/or the S1 interface setupresponse carries an inter-base station coordinated service identifier.

Preferably, the receiving unit 22 is further configured to receiverelationship information of the secondary base station and the primarybase station from an OAM, and the sending unit 21 is further configuredto send the first message to the secondary base station.

Preferably, the sending unit 21 is further configured to send anInternet Protocol IP address and a tunnel endpoint identifier TEID ofthe primary base station to the secondary base station; and the exchangeunit 23 is configured to: receive uplink data that is sent by thesecondary base station and received from user equipment UE, and send theuplink data to an S-GW; and/or forward, to the secondary base station,downlink data from the S-GW, so that the secondary base station sendsthe downlink data to the UE.

Preferably, the sending unit 21 is further configured to send, to anS-GW by using an MME, a received downlink TNL address and a received GTPTEID of the secondary base station that are sent by the secondary basestation, and send an uplink TNL address and a GTP TEID of the S-GW tothe secondary base station, so that the secondary base station sends, tothe S-GW, received uplink data sent by the UE, and the secondary basestation sends, to the UE, received downlink data sent by the S-GW.

The data exchange apparatus in this embodiment implements that asecondary base station initiates an S1 interface setup request aftertriggering by a primary base station or configuration by an OAM, so asto set up an S1 interface that can be used to perform bidirectional datatransmission, thereby implementing that bidirectional data exchange isperformed between the primary base station and the secondary basestation by using the S1 interface.

FIG. 11 is a schematic diagram of a data exchange apparatus according toa third embodiment of the present invention. The apparatus in thisembodiment is a primary base station, and as shown in the figure, thedata exchange apparatus in this embodiment specifically includes: asending unit 31, a receiving unit 32, and an exchange unit 33.

The sending unit 31 is configured to send an X2 handover request messageto a secondary base station, where the X2 handover request messageincludes tunnel address information allocated by the primary basestation to user equipment UE; the receiving unit 32 is configured toreceive an X2 handover request response sent by the secondary basestation; and the exchange unit 33 is configured to perform data exchangewith the secondary base station by using an X2 interface.

The exchange unit 33 may include the sending unit 31 and/or thereceiving unit 32, or may be another unit having a sending and/orreceiving function.

Specifically, the tunnel address information includes: a TNL address anda GTP TEID that are allocated by the primary base station to the UE. TheX2 handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

Preferably, the apparatus further includes a control unit 34, configuredto update or release an X2 interface association or a GTP tunnel relatedto the UE, and the sending unit 31 is further configured to send anupdate or release message to the secondary base station, so that thesecondary base station updates or releases the X2 interface associationor the GTP tunnel of the UE. The update or release message carries theinter-base station coordinated service identifier and a beareridentifier.

For the data exchange apparatus in this embodiment, an X2 handoverrequest message includes tunnel address information allocated by aprimary base station to user equipment UE, so that a GTP tunnel from asecondary base station to the primary base station can be set up, thatis, a bidirectional GTP tunnel is set up; therefore, an X2 interface setup in this embodiment can be used to perform bidirectional datatransmission, thereby implementing bidirectional data exchange betweenthe primary base station and the secondary base station.

FIG. 12 is a schematic diagram of a data exchange apparatus according toa fourth embodiment of the present invention. The apparatus in thisembodiment is a secondary base station, and as shown in the figure, thedata exchange apparatus in this embodiment specifically includes: areceiving unit 41, a sending unit 42, and an exchange unit 43.

The receiving unit 41 is configured to receive an X2 handover requestmessage sent by a primary base station, where the X2 handover requestmessage includes tunnel address information allocated by the primarybase station to user equipment UE; the sending unit 42 is configured tosend an X2 handover request response to the primary base station; andthe exchange unit 43 is configured to perform data exchange with theprimary base station by using an X2 interface.

The exchange unit 43 may include the receiving unit 41 and/or thesending unit 42, or may be another unit having a sending and/orreceiving function.

Specifically, the tunnel address information includes: a TNL address anda GTP TEID that are allocated by the primary base station to the UE. TheX2 handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

Preferably, the receiving unit 41 is configured to receive an update orrelease message sent by the primary base station; and the apparatusfurther includes a control unit 44, configured to update or release anX2 interface association or a GTP tunnel of the UE. The update orrelease message carries the inter-base station coordinated serviceidentifier and a bearer identifier.

For the data exchange apparatus in this embodiment, an X2 handoverrequest message includes tunnel address information allocated by aprimary base station to user equipment UE, so that a GTP tunnel from asecondary base station to the primary base station can be set up, thatis, a bidirectional GTP tunnel is set up; therefore, an X2 interface setup in this embodiment can be used to perform bidirectional datatransmission, thereby implementing bidirectional data exchange betweenthe secondary base station and the primary base station.

FIG. 13 is a schematic diagram of a data exchange apparatus according toa fifth embodiment of the present invention. The apparatus in thisembodiment is a primary base station, and as shown in the figure, thedata exchange apparatus in this embodiment specifically includes: asending unit 51, a receiving unit 52, and an exchange unit 53.

The sending unit 51 is configured to send a request of setting up an X3interface to a secondary base station, where the X3 interface has acapability of bidirectional data communication; the receiving unit 52 isconfigured to receive a response of setting up the X3 interface sent bythe secondary base station; and the exchange unit 53 is configured toperform bidirectional data exchange with the secondary base station byusing the X3 interface.

The exchange unit 53 may include the sending unit 51 and/or thereceiving unit 52, or may be another unit having a sending and/orreceiving function.

Specifically, the request of setting up the X3 interface carries aninter-base station coordinated service identifier, and/or the responseof setting up the X3 interface carries an inter-base station coordinatedservice identifier. The X3 interface includes: an S1 interface.

Preferably, the sending unit 51 is further configured to send anInternet Protocol IP address and a tunnel endpoint identifier TEID ofthe primary base station to the secondary base station; and the exchangeunit 53 is specifically configured to: receive uplink data that is sentby user equipment UE and forwarded by the secondary base station, andsend the uplink data to a serving gateway S-GW; and send, to thesecondary base station, downlink data sent by the S-GW, so that thesecondary base station sends the downlink data to the UE.

Preferably, the sending unit 51 is further configured to send a downlinkTNL address and a GTP TEID of the secondary base station to an S-GW byusing an MME, and send an uplink TNL address and a GTP TEID of the S-GWto the secondary base station, so that the secondary base station sends,to the S-GW, received uplink data sent by UE, and sends, to the UE,received downlink data sent by the S-GW.

For the data exchange apparatus in this embodiment, a primary basestation sends a request of setting up an X3 interface, so that an X3interface from the primary base station to a secondary base station canbe set up, and the X3 interface may be implemented by an existinginterface, for example, an S1 interface, or may be a newly definedinterface having a capability of bidirectional data communication.Therefore, the X3 interface set up in this embodiment can be used toperform bidirectional data transmission, thereby implementingbidirectional data exchange between the primary base station and thesecondary base station.

FIG. 14 is a schematic diagram of a data exchange apparatus according toa sixth embodiment of the present invention. The apparatus in thisembodiment is a secondary base station, and as shown in the figure, thedata exchange apparatus in this embodiment specifically includes: areceiving unit 61, a sending unit 62, and an exchange unit 63.

The receiving unit 61 is configured to receive a request of setting upan X3 interface sent by a primary base station, where the X3 interfacehas a capability of bidirectional data communication; the sending unit62 is configured to send a response of setting up the X3 interface tothe primary base station; and the exchange unit 63 is configured toperform bidirectional data exchange with the primary base station byusing the X3 interface.

The exchange unit 63 may include the receiving unit 61 and/or thesending unit 62, or may be another unit having a sending and/orreceiving function.

Specifically, the request of setting up the X3 interface carries aninter-base station coordinated service identifier, and/or the responseof setting up the X3 interface carries an inter-base station coordinatedservice identifier. The X3 interface includes: an S1 interface.

Preferably, the receiving unit 61 is further configured to receive anInternet Protocol IP address and a tunnel endpoint identifier TED of theprimary base station that are sent by the primary base station; and theexchange unit 63 is specifically configured to: send, to the primarybase station, forwarded uplink data sent by user equipment UE, so thatthe primary base station sends the uplink data to a serving gatewayS-GW; and receive downlink data that is sent by the S-GW and then sentby the primary base station, so that the secondary base station sendsthe downlink data to the UE.

Preferably, the exchange unit 63 is further configured to: receive anuplink transport network layer address TNL address and a General PacketRadio Service Tunneling Protocol tunnel endpoint identifier GTP TED ofan S-GW that are sent by the primary base station; send, to the S-GW,received uplink data sent by UE; and send, to the UE, received downlinkdata from the S-GW.

For the data exchange apparatus in this embodiment, a secondary basestation receives a request of setting up an X3 interface sent by aprimary base station, so that an X3 interface from the secondary basestation to the primary base station can be set up, and the X3 interfacemay be implemented by an existing interface, for example, an S1interface, or may be a newly defined interface having a capability ofbidirectional data communication. Therefore, the X3 interface set up inthis embodiment can be used to perform bidirectional data transmission,thereby implementing bidirectional data exchange between the secondarybase station and the primary base station.

FIG. 15 is a schematic diagram of a data exchange apparatus according toa seventh embodiment of the present invention. The apparatus in thisembodiment is a mobility management entity MME, and as shown in thefigure, the data exchange apparatus in this embodiment specificallyincludes: a receiving unit 71 and a sending unit 72.

The receiving unit 71 is configured to receive a first message sent by aprimary base station, where the first message is used for requesting asecondary base station to collaborate with the primary base station toserve user equipment (UE), and the first message includes an identifierof the UE and an identifier of the secondary base station; the sendingunit 72 is configured to send a second message to the secondary basestation, where the second message is used for requesting the secondarybase station to collaborate with the primary base station to serve theUE, and the second message includes the identifier of the UE; thereceiving unit 71 is further configured to receive a first responsereturned by the secondary base station, where the first response is usedfor indicating information that the secondary base station agrees tocollaborate with the primary base station to serve the UE; and thesending unit 72 is further configured to send a second response to theprimary base station, so that the primary base station and the secondarybase station work together to serve the UE.

Preferably, the sending unit 72 is further configured to notify an S-GWcorresponding to the UE of address information of the secondary basestation, and notify the secondary base station of address information ofthe S-GW, so that the secondary base station performs data exchange withthe S-GW for the UE. The address information of the secondary basestation includes: a TNL address and a GTP-TEID of the secondary basestation, and the address information of the S-GW includes: a TNL addressand a GTP-TEID of the S-GW.

For the data exchange apparatus in this embodiment, a network elementMME of a core network is used to assist in data exchange, therebyimplementing that a primary base station and a secondary base stationwork together to serve UE. The secondary base station is used todirectly perform data transmission with an S-GW, so that for aninter-base station coordinated service, different base stations mayserve different bearers, thereby improving service quality for UE.Existing messages are reused to the maximum degree.

FIG. 16 is a schematic diagram of a data exchange apparatus according toan eighth embodiment of the present invention. The apparatus in thisembodiment is a secondary base station, and as shown in the figure, thedata exchange apparatus in this embodiment specifically includes: areceiving unit 81 and a sending unit 82.

The receiving unit 81 is configured to receive a second message sent byan MME, where the second message is used for requesting the secondarybase station to collaborate with a primary base station to serve UE, andthe second message includes an identifier of the UE; and the sendingunit 82 is configured to send a first response to the MME, where thefirst response is used for indicating information that the secondarybase station agrees to collaborate with the primary base station toserve the UE, so that the MME sends a second response to the primarybase station, where the second response is used for notifying that theprimary base station works together with the secondary base station toserve the UE.

Preferably, the receiving unit 81 is further configured to receiveaddress information, sent by the MME, of an S-GW corresponding to theUE; and the apparatus further includes an exchange unit 83, configuredto perform, according to the address information of the S-GW, dataexchange with the S-GW for the UE. The address information of the S-GWincludes: a TNL address and a GTP-TEID of the S-GW.

The exchange unit 83 may include the receiving unit 81 and/or thesending unit 82, or may be another unit having a sending and/orreceiving function.

Preferably, the exchange unit 83 is further configured to send, to anS-GW, received uplink data sent by the UE, and send, to the UE, receiveddownlink data sent by the S-GW.

For the data exchange apparatus in this embodiment, a network elementMME of a core network is used to assist in data exchange, therebyimplementing that a primary base station and a secondary base stationwork together to serve UE. The secondary base station is used todirectly perform data transmission with an S-GW, so that for aninter-base station coordinated service, different base stations mayserve different bearers, thereby improving service quality for UE.Existing messages are reused to the maximum degree.

FIG. 17 is a schematic diagram of another data exchange apparatusaccording to a first embodiment of the present invention. The apparatusin this embodiment is a secondary base station, and as shown in thefigure, this embodiment includes a network interface 111, a processor112, and a memory 113. Optionally, the apparatus further includes asystem bus 114, configured to connect the network interface 111, theprocessor 112, and the memory 113. Optionally, the network interface 111and the processor 112 are connected, and the processor 112 and thememory 113 are connected.

The network interface 111 is configured to communicate with an externaldevice.

The memory 113 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 113 has a software module and adevice driver program. The software module can perform variousfunctional modules in the foregoing methods of the present invention.The device driver program may be a network and interface driver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 113,and is then accessed by the processor 112 and executes the followinginstructions:

an instruction used for receiving a first message sent by a primary basestation, or receiving relationship information of the secondary basestation and a primary base station configured by an operation,administration and maintenance system (OAM), where the first message isused for notifying the secondary base station to set up an S1 interface;

an instruction used for sending an S1 interface setup request to theprimary base station;

an instruction used for receiving an S1 interface setup response sent bythe primary base station; and

an instruction used for performing exchange with the primary basestation by using the S1 interface; and

the processor is configured to execute an application program.

Specifically, the first message carries an inter-base stationcoordinated service identifier, the S1 interface setup request carriesan inter-base station coordinated service identifier, and/or the S1interface setup response carries an inter-base station coordinatedservice identifier. The first message is sent by the primary basestation after the primary base station receives the relationshipinformation of the secondary base station and the primary base stationfrom the OAM.

Preferably, the application program further includes: an instructionused for receiving an Internet Protocol (IP) address and a tunnelendpoint identifier (TEID) of the primary base station that are sent bythe primary base station.

Preferably, the instruction used for performing exchange with theprimary base station by using the S1 interface includes: an instructionused for sending, to the primary base station, received uplink data sentby user equipment UE, so that the primary base station sends the uplinkdata to an S-GW; and/or an instruction used for receiving downlink datathat is from the S-GW and is forwarded by the primary base station, andsending the downlink data to the UE.

Preferably, the application program further includes: an instructionused for sending, to an S-GW by using an MME, a received downlink TNLaddress and a received GTP TEID of the secondary base station that aresent by the secondary base station, and an instruction used for sendingan uplink TNL address and a GTP TEID of the S-GW to the secondary basestation, so that the secondary base station sends, to the S-GW, receiveduplink data sent by the UE, and the secondary base station sends, to theUE, received downlink data sent by the S-GW.

The data exchange apparatus in this embodiment implements that asecondary base station initiates an S1 interface setup request aftertriggering by a primary base station or configuration by an OAM, so asto set up an S1 interface that can be used to perform bidirectional datatransmission, thereby implementing that bidirectional data exchange isperformed between the primary base station and the secondary basestation by using the S1 interface.

FIG. 18 is a schematic diagram of another data exchange apparatusaccording to a second embodiment of the present invention. The apparatusin this embodiment is a primary base station, and as shown in thefigure, this embodiment includes a network interface 121, a processor122, and a memory 123. Optionally, the apparatus further includes asystem bus 124, configured to connect the network interface 121, theprocessor 122, and the memory 123. Optionally, the network interface 121and the processor 122 are connected, and the processor 122 and thememory 123 are connected.

The network interface 121 is configured to communicate with an externaldevice.

The memory 123 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 123 has a software module and adevice driver program. The software module can perform variousfunctional modules in the foregoing methods of the present invention.The device driver program may be a network and interface driver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 123,and is then accessed by the processor 122 and executes the followinginstructions:

an instruction used for sending a first message to a secondary basestation, where the first message is used for notifying the secondarybase station to set up an S1 interface;

an instruction used for receiving an S1 interface setup request sent bythe secondary base station;

an instruction used for sending an S1 interface setup response to thesecondary base station; and

an instruction used for performing exchange with the secondary basestation by using the S1 interface; and

the processor is configured to execute an application program.

Preferably, the first message carries an inter-base station coordinatedservice identifier, the S1 interface setup request carries an inter-basestation coordinated service identifier, and/or the S1 interface setupresponse carries an inter-base station coordinated service identifier.

Preferably, the instruction used for sending a first message to asecondary base station includes: an instruction used for receivingrelationship information of the secondary base station and the primarybase station from an OAM, and an instruction used for sending the firstmessage to the secondary base station.

Preferably, the application program further includes: an instructionused for sending an Internet Protocol IP address and a tunnel endpointidentifier TED of the primary base station to the secondary basestation.

Preferably, the instruction used for performing exchange with thesecondary base station by using the S1 interface includes: aninstruction used for receiving uplink data that is sent by the secondarybase station and received from user equipment UE, and an instructionused for sending the uplink data to an S-GW; and/or an instruction usedfor forwarding, to the secondary base station, downlink data from theS-GW, so that the secondary base station sends the downlink data to theUE.

Preferably, the application program further includes: an instructionused for sending, to an S-GW by using an MME, a received downlink TNLaddress and a received GTP TEID of the secondary base station that aresent by the secondary base station, and an instruction used for sendingan uplink TNL address and a GTP TEID of the S-GW to the secondary basestation, so that the secondary base station sends, to the S-GW, receiveduplink data sent by the UE, and the secondary base station sends, to theUE, received downlink data sent by the S-GW.

The data exchange apparatus in this embodiment implements that asecondary base station initiates an S1 interface setup request aftertriggering by a primary base station or configuration by an OAM, so asto set up an S1 interface that can be used to perform bidirectional datatransmission, thereby implementing that bidirectional data exchange isperformed between the primary base station and the secondary basestation by using the S1 interface.

FIG. 19 is a schematic diagram of another data exchange apparatusaccording to a third embodiment of the present invention. As shown inthe figure, the apparatus in this embodiment is a primary base station,and this embodiment includes a network interface 131, a processor 132,and a memory 133. Optionally, the apparatus further includes a systembus 134, configured to connect the network interface 131, the processor132, and the memory 133. Optionally, the network interface 131 and theprocessor 132 are connected, and the processor 132 and the memory 133are connected.

The network interface 131 is configured to communicate with an externaldevice.

The memory 133 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 133 has a software module and adevice driver program. The software module can perform variousfunctional modules in the foregoing methods of the present invention.The device driver program may be a network and interface driver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 133,and is then accessed by the processor 132 and executes the followinginstructions:

an instruction used for sending an X2 handover request message to asecondary base station, where the X2 handover request message includestunnel address information allocated by the primary base station to userequipment UE;

an instruction used for receiving an X2 handover request response sentby the secondary base station; and

an instruction used for performing data exchange with the secondary basestation by using an X2 interface; and

the processor is configured to execute an application program.

Specifically, the tunnel address information includes: a TNL address anda GTP TEID that are allocated by the primary base station to the UE. TheX2 handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

Preferably, the application program further includes: an instructionused for updating or releasing an X2 interface association or a GTPtunnel related to the UE, and sending an update or release message tothe secondary base station, so that the secondary base station updatesor releases the X2 interface association or the General Packet RadioService Tunneling Protocol GTP tunnel of the UE. The update or releasemessage carries the inter-base station coordinated service identifierand a bearer identifier.

For the data exchange apparatus in this embodiment, an X2 handoverrequest message includes tunnel address information allocated by aprimary base station to user equipment UE, so that a GTP tunnel from asecondary base station to the primary base station can be set up, thatis, a bidirectional GTP tunnel is set up; therefore, an X2 interface setup in this embodiment can be used to perform bidirectional datatransmission, thereby implementing bidirectional data exchange betweenthe primary base station and the secondary base station.

FIG. 20 is a schematic diagram of another data exchange apparatusaccording to a fourth embodiment of the present invention. The apparatusin this embodiment is a secondary base station, and as shown in thefigure, this embodiment includes a network interface 141, a processor142, and a memory 143. Optionally, the apparatus further includes asystem bus 144, configured to connect the network interface 141, theprocessor 142, and the memory 143. Optionally, the network interface 141and the processor 142 are connected, and the processor 142 and thememory 143 are connected.

The network interface 141 is configured to communicate with an externaldevice.

The memory 143 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 143 has a software module and adevice driver program. The software module can perform variousfunctional modules in the foregoing methods of the present invention.The device driver program may be a network and interface driver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 143,and is then accessed by the processor 142 and executes the followinginstructions:

an instruction used for receiving an X2 handover request message sent bya primary base station, where the X2 handover request message includestunnel address information allocated by the primary base station to userequipment UE;

an instruction used for sending an X2 handover request response to theprimary base station; and

an instruction used for performing data exchange with the primary basestation by using an X2 interface; and

the processor is configured to execute an application program.

Specifically, the tunnel address information includes: a TNL address anda GTP TEID that are allocated by the primary base station to the UE. TheX2 handover request message carries an inter-base station coordinatedservice identifier; and/or the X2 handover request response carries aninter-base station coordinated service identifier.

Preferably, the application program further includes: an instructionused for receiving an update or release message sent by the primary basestation, and updating or releasing an X2 interface association or aGeneral Packet Radio Service (GPRS) Tunneling Protocol (GTP) tunnel ofthe UE. The update or release message carries the inter-base stationcoordinated service identifier and a bearer identifier.

For the data exchange apparatus in this embodiment, an X2 handoverrequest message includes tunnel address information allocated by aprimary base station to user equipment UE, so that a GTP tunnel from asecondary base station to the primary base station can be set up, thatis, a bidirectional GTP tunnel is set up; therefore, an X2 interface setup in this embodiment can be used to perform bidirectional datatransmission, thereby implementing bidirectional data exchange betweenthe secondary base station and the primary base station.

FIG. 21 is a schematic diagram of another data exchange apparatusaccording to a fifth embodiment of the present invention. The apparatusin this embodiment is a primary base station, and as shown in thefigure, this embodiment includes a network interface 151, a processor152, and a memory 153. Optionally, the apparatus further includes asystem bus 154, configured to connect the network interface 151, theprocessor 152, and the memory 153. Optionally, the network interface 151and the processor 152 are connected, and the processor 152 and thememory 153 are connected.

The network interface 151 is configured to communicate with an externaldevice.

The memory 153 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 153 has a software module and adevice driver program. The software module can perform variousfunctional modules in the foregoing methods of the present invention.The device driver program may be a network and interface driver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 153,and is then accessed by the processor 152 and executes the followinginstructions:

an instruction used for sending a request of setting up an X3 interfaceto a secondary base station, where the X3 interface has a capability ofbidirectional data communication;

an instruction used for receiving a response of setting up the X3interface sent by the secondary base station; and

an instruction used for performing bidirectional data exchange with thesecondary base station by using the X3 interface; and

the processor is configured to execute an application program.

Specifically, the request of setting up the X3 interface carries aninter-base station coordinated service identifier, and/or, the responseof setting up the X3 interface carries an inter-base station coordinatedservice identifier. The X3 interface includes: an S1 interface.

Preferably, the application program further includes an instruction thatmay be used for enabling the processor and a system to perform thefollowing process: sending, by the primary base station, an InternetProtocol (IP) address and a tunnel endpoint identifier (TED) of theprimary base station to the secondary base station.

Preferably, the application program further includes: an instructionused for sending an Internet Protocol (IP) address and a tunnel endpointidentifier (TEID) of the primary base station to the secondary basestation. The instruction used for performing bidirectional data exchangewith the secondary base station by using the X3 interface includes: aninstruction used for receiving uplink data that is sent by userequipment UE and forwarded by the secondary base station, and sendingthe uplink data to a serving gateway S-GW; and an instruction used forsending, to the secondary base station, downlink data sent by the S-GW,so that the secondary base station sends the downlink data to the UE.

Preferably, after the primary base station receives the response ofsetting up the X3 interface sent by the secondary base station, theapplication program further includes: an instruction used for sending adownlink transport network layer address TNL address and a GeneralPacket Radio Service (GPRS) Tunneling Protocol (GTP) tunnel endpointidentifier (GTP TED) of the secondary base station to an S-GW by using amobility management entity MME, and an instruction used for sending anuplink TNL address and a GTP TEID of the S-GW to the secondary basestation, so that the secondary base station sends, to the S-GW, receiveduplink data sent by UE, and an instruction used for sending, to the UE,received downlink data sent by the S-GW.

For the data exchange apparatus in this embodiment, a primary basestation sends a request of setting up an X3 interface, so that an X3interface from the primary base station to a secondary base station canbe set up, and the X3 interface may be implemented by an existinginterface, for example, an S1 interface, or may be a newly definedinterface having a capability of bidirectional data communication.Therefore, the X3 interface set up in this embodiment can be used toperform bidirectional data transmission, thereby implementingbidirectional data exchange between the primary base station and thesecondary base station.

FIG. 22 is a schematic diagram of another data exchange apparatusaccording to a sixth embodiment of the present invention. The apparatusin this embodiment is a secondary base station, and as shown in thefigure, the apparatus includes a network interface 161, a processor 162,and a memory 163. Optionally, the apparatus further includes a systembus 164, configured to connect the network interface 161, the processor162, and the memory 163. Optionally, the network interface 161 and theprocessor 162 are connected, and the processor 162 and the memory 163are connected.

The network interface 161 is configured to communicate with an externaldevice.

The memory 163 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 163 has a software module and adevice driver program. The software module may include variousfunctional modules that can perform the foregoing methods of the presentinvention. The device driver program may be a network and interfacedriver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 163,and is then accessed by the processor 162 and executes the followinginstructions:

an instruction used for receiving a request of setting up an X3interface sent by a primary base station, where the X3 interface has acapability of bidirectional data communication;

an instruction used for sending a response of setting up the X3interface to the primary base station; and

an instruction used for performing bidirectional data exchange with theprimary base station by using the X3 interface; and

the processor is configured to execute an application program.

Specifically, the request of setting up the X3 interface carries aninter-base station coordinated service identifier, and/or the responseof setting up the X3 interface carries an inter-base station coordinatedservice identifier. The X3 interface includes: an S1 interface.

Preferably, the application program further includes an instruction thatmay be used for enabling the processor and a system to perform thefollowing process: receiving an Internet Protocol IP address and atunnel endpoint identifier TEID of the primary base station that aresent by the primary base station.

Preferably, the application program further includes an instruction usedfor receiving an Internet Protocol IP address and a tunnel endpointidentifier TED of the primary base station that are sent by the primarybase station. The instruction used for performing bidirectional dataexchange with the primary base station by using the X3 interfaceincludes: an instruction used for sending, to the primary base station,uplink data from user equipment UE, so that the primary base stationsends the uplink data to a serving gateway S-GW; and an instruction usedfor receiving downlink data that is from the S-GW and is sent by theprimary base station, and sending the downlink data to the UE.

Preferably, the application program further includes: an instructionused for receiving an uplink transport network layer address TNL addressand a General Packet Radio Service Tunneling Protocol tunnel endpointidentifier GTP TEID of an S-GW that are sent by the primary basestation, sending, to the S-GW, received uplink data sent by the UE, andsending, to the UE, received downlink data from the S-GW.

For the data exchange apparatus in this embodiment, a secondary basestation receives a request of setting up an X3 interface sent by aprimary base station, so that an X3 interface from the secondary basestation to the primary base station can be set up, and the X3 interfacemay be implemented by an existing interface, for example, an S1interface, or may be a newly defined interface having a capability ofbidirectional data communication. Therefore, the X3 interface set up inthis embodiment can be used to perform bidirectional data transmission,thereby implementing bidirectional data exchange between the secondarybase station and the primary base station.

FIG. 23 is a schematic diagram of another data exchange apparatusaccording to a seventh embodiment of the present invention. Theapparatus in this embodiment is a mobility management entity MME, and asshown in the figure, this embodiment includes a network interface 171, aprocessor 172, and a memory 173. Optionally, the apparatus furtherincludes a system bus 174, configured to connect the network interface171, the processor 172, and the memory 173. Optionally, the networkinterface 171 and the processor 172 are connected, and the processor 172and the memory 173 are connected.

The network interface 171 is configured to communicate with an externaldevice.

The memory 173 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 173 has a software module and adevice driver program. The software module can perform variousfunctional modules in the foregoing methods of the present invention.The device driver program may be a network and interface driver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 173,and is then accessed by the processor 172 and executes the followinginstructions:

an instruction used for receiving a first message sent by a primary basestation, where the first message is used for requesting a secondary basestation to collaborate with the primary base station to serve userequipment UE;

an instruction used for sending a second message to the secondary basestation, where the second message is used for requesting the secondarybase station to collaborate with the primary base station to serve theUE;

an instruction used for receiving a first response returned by thesecondary base station, where the first response carries informationthat the secondary base station agrees to collaborate with the primarybase station to serve the UE; and

an instruction used for sending a second response to the primary basestation, so that the primary base station and the secondary base stationwork together to serve the UE; and

the processor is configured to execute an application program.

Preferably, the application program further includes an instruction usedfor notifying a serving gateway S-GW corresponding to the UE of addressinformation of the secondary base station, and notifying the secondarybase station of address information of the S-GW, so that the secondarybase station performs data exchange with the S-GW for the UE. Theaddress information of the secondary base station includes: a transportnetwork layer address TNL address and a General Packet Radio ServiceTunneling Protocol tunnel endpoint identifier GTP-TEID of the secondarybase station, and the address information of the S-GW includes: a TNLaddress and a GTP-TEID of the S-GW.

For the data exchange apparatus in this embodiment, a network elementMME of a core network is used to assist in data exchange, therebyimplementing that a primary base station and a secondary base stationwork together to serve UE. The secondary base station is used todirectly perform data transmission with an S-GW, so that for aninter-base station coordinated service, different base stations mayserve different bearers, thereby improving service quality for UE.Existing messages are reused to the maximum degree.

FIG. 24 is a schematic diagram of another data exchange apparatusaccording to an eighth embodiment of the present invention. Theapparatus in this embodiment is a secondary base station, and as shownin the figure, this embodiment includes a network interface 181, aprocessor 182, and a memory 183. Optionally, the apparatus furtherincludes a system bus 184, configured to connect the network interface181, the processor 182, and the memory 183. Optionally, the networkinterface 181 and the processor 182 are connected, and the processor 182and the memory 183 are connected.

The network interface 181 is configured to communicate with an externaldevice.

The memory 183 may be a permanent memory, for example, a hard disk driveand a flash memory, and the memory 183 has a software module and adevice driver program. The software module can perform variousfunctional modules in the foregoing methods of the present invention.The device driver program may be a network and interface driver program.

When being started, a software component, for example, the softwaremodule and/or the device driver program, is loaded to the memory 183,and is then accessed by the processor 182 and executes the followinginstructions:

an instruction used for receiving a second message sent by a mobilitymanagement entity MME, where the second message is used for requestingthe secondary base station to collaborate with a primary base station toserve user equipment UE; and

an instruction used for sending a first response to the MME, where thefirst response carries information that the secondary base stationagrees to collaborate with the primary base station to serve the UE, sothat the MME sends a second response to the primary base station, andthe second response is used for notifying that the primary base stationworks together with the secondary base station to serve the UE; and

the processor is configured to execute an application program.

Preferably, after the secondary base station sends the first response tothe MME, the application program further includes: an instruction usedfor receiving address information, sent by the MME, of a serving gatewayS-GW corresponding to the UE; and an instruction used for performing,according to the address information of the S-GW, data exchange with theS-GW for the UE. The address information of the S-GW includes: atransport network layer address TNL address and a General Packet RadioService (GPRS) Tunneling Protocol (GTP) tunnel endpoint identifier(GTP-TEID) of the S-GW.

Preferably, the instruction used for performing, according to theaddress information of the S-GW, data exchange with the S-GW for the UEincludes: an instruction used for sending, to the S-GW, received uplinkdata from the UE, and sending, to the UE, received downlink data fromthe S-GW.

For the data exchange apparatus in this embodiment, a network elementMME of a core network is used to assist in data exchange, therebyimplementing that a primary base station and a secondary base stationwork together to serve UE. The secondary base station is used todirectly perform data transmission with an S-GW, so that for aninter-base station coordinated service, different base stations mayserve different bearers, thereby improving service quality for UE.Existing messages are reused to the maximum degree.

A person skilled in the art may be further aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware, computer software, or a combination thereof. Toclearly describe the interchangeability between the hardware and thesoftware, the foregoing has generally described compositions and stepsof each example according to functions. Whether the functions areperformed by hardware or software depends on particular applications anddesign constraint conditions of the technical solutions. A personskilled in the art may use different methods to implement the describedfunctions for each particular application, but it should not beconsidered that the implementation goes beyond the scope of the presentinvention.

Steps of methods or algorithms described in the embodiments disclosed inthis specification may be implemented by hardware, a software moduleexecuted by a processor, or a combination thereof. The software modulemay reside in a random access memory (RAM), a memory, a read-only memory(ROM), an electrically programmable ROM, an electrically erasableprogrammable ROM, a register, a hard disk, a removable disk, a CD-ROM,or a storage medium in any other forms well known in the art.

In the foregoing specific implementation manners, the objective,technical solutions, and benefits of the present invention are furtherdescribed in detail. It should be understood that the foregoingdescriptions are merely specific implementation manners of the presentinvention, but are not intended to limit the protection scope of thepresent invention. Any modification, equivalent replacement, orimprovement made without departing from the spirit and principle of thepresent invention should fall within the protection scope of the presentinvention.

What is claimed is:
 1. A data exchange apparatus, comprising: atransmitter configured to send, to a secondary base station, a requestfor setting up an interface that is capable of bidirectional signalingcommunication; a receiver configured to receive a response for settingup the interface from the secondary base station; and a processorcoupled to the receiver and the transmitter and configured to performbidirectional signaling exchange with the secondary base station usingthe interface, wherein the transmitter is further configured to: send adownlink transport network layer (TNL) address and a General PacketRadio Service Tunneling Protocol tunnel endpoint identifier (GTP TEID)of the secondary base station to a user plane entity using a mobilitymanagement entity (MME); and send an uplink TNL address and a GTP TEIDof the user plane entity to the secondary base station.
 2. A dataexchange apparatus, comprising: a receiver configured to receive, from aprimary base station, a request for setting up an interface that iscapable of bidirectional signaling communication; a transmitterconfigured to send a response for setting up the interface to theprimary base station; and a processor coupled to the receiver and thetransmitter and configured to perform bidirectional signaling exchangewith the primary base station using the interface, wherein the receiveris further configured to: receive an uplink transport network layer(TNL) address and a General Packet Radio Service Tunneling Protocoltunnel endpoint identifier (GTP TEID) of a user plane entity sent by theprimary base station, and wherein the transmitter is further configuredto: send, to the user plane entity, received uplink data from a userequipment (UE); and send, to the UE, received downlink data from theuser plane entity.
 3. A data exchange method, comprising: sending, by aprimary base station to a secondary base station, a request for settingup an interface that is capable of bidirectional data communication;receiving, by the primary base station, a response for setting up theinterface from the secondary base station; transmitting, by the primarybase station, a first internet protocol (IP) address and a first GeneralPacket Radio Service Tunneling Protocol tunnel endpoint identifier (GTPTEID) of the primary base station to the secondary base station;transmitting, by the primary base station, a second IP address and asecond GTP TEID of the primary base station to a user plane entity;receiving, by the primary base station, uplink data according to thefirst IP address and the first GTP TEID; and receiving, by the primarybase station, downlink data according to the second IP address and thesecond GTP TEID.
 4. The method of claim 3, wherein after receiving, bythe primary base station, the uplink data according to the first IPaddress and the first GTP TEID, the method further comprisestransmitting, by the primary base station, the uplink data to the userplane entity.
 5. The method of claim 3, wherein after receiving, by theprimary base station, the downlink data according to the second IPaddress and the second GTP TEID, the method further comprisestransmitting, by the primary base station, the downlink data to thesecondary base station.
 6. The method claim 4, wherein after receiving,by the primary base station, the downlink data according to the secondIP address and the second GTP TEID, the method further comprisestransmitting, by the primary base station, the downlink data to thesecondary base station.
 7. A data exchange apparatus, comprising: atransmitter configured to: send, to a secondary base station, a requestfor setting up an interface that is capable of bidirectional datacommunication; transmit a first internet protocol (IP) address and afirst General Packet Radio Service Tunneling Protocol tunnel endpointidentifier (GTP TEID) of a primary base station to the secondary basestation; and transmit a second IP address and a second GTP TEID of theprimary base station to a user plane entity; and a receiver coupled tothe transmitter and configured to: receive a response for setting up theinterface from the secondary base station; receive uplink data accordingto the first IP address and the first GTP TEID; and receive downlinkdata according to the second IP address and the second GTP TEID.
 8. Theapparatus of claim 7, wherein the transmitter is further configured totransmit the uplink data to the user plane entity.
 9. The apparatus ofclaim 7, wherein the transmitter is further configured to transmit thedownlink data to the secondary base station.
 10. A data exchange method,comprising: sending, to a secondary base station, a request for settingup an interface that is capable of bidirectional signalingcommunication; receiving a response for setting up the interface fromthe secondary base station; sending a downlink transport network layer(TNL) address and a General Packet Radio Service Tunneling Protocoltunnel endpoint identifier (GTP TEID) of the secondary base station to auser plane entity using a mobility management entity (MME); sending anuplink TNL address and a GTP TEID of the user plane entity to thesecondary base station; and performing bidirectional signaling exchangewith the secondary base station using the interface.
 11. A data exchangemethod, comprising: receiving, from a primary base station, a requestfor setting up an interface that is capable of bidirectional signalingcommunication; sending a response for setting up the interface to theprimary base station; receiving an uplink transport network layer (TNL)address and a General Packet Radio Service Tunneling Protocol tunnelendpoint identifier (GTP TEID) of a user plane entity from the primarybase station; sending, to the user plane entity, received uplink datafrom a user equipment (UE); sending, to the UE, received downlink datafrom the user plane entity; and performing bidirectional signalingexchange with the primary base station using the interface.
 12. Themethod of claim 11, wherein the method is implemented by a secondarybase station.
 13. The method of claim 12, further comprising thesecondary base station working together with the primary base station tosimultaneously provide service for the UE.
 14. The data exchangeapparatus of claim 1, wherein the request for setting up the interfacecomprises an inter-base station coordinated service identifier.
 15. Thedata exchange apparatus of claim 14, wherein the response for setting upthe interface comprises the inter-base station coordinated serviceidentifier.
 16. The data exchange apparatus of claim 1, wherein theresponse for setting up the interface comprises an inter-base stationcoordinated service identifier.
 17. The data exchange apparatus of claim2, wherein the request for setting up the interface comprises aninter-base station coordinated service identifier.
 18. The data exchangeapparatus of claim 17, wherein the response for setting up the interfacecomprises the inter-base station coordinated service identifier.
 19. Thedata exchange apparatus of claim 2, wherein the response for setting upthe interface comprises an inter-base station coordinated serviceidentifier.